Computer Overview 2 PDF

System Software & Computing Concepts Overview of Computer Systems  Topics we will cover Components of a Computer System Hardware Software Communication Compu...

System Software & Computing Concepts Overview of Computer Systems  Topics we will cover Components of a Computer System Hardware Software Communication Computer System Virtualization Protocols and Standards Module Code & Module Title Slide Title 2  Learning Outcomes At the end of this section, YOU should be able to: Describe the basic building blocks of a computer system Identify the different types of computer systems Describe the different Protocols and Standards in computer systems Module Code & Module Title Slide Title 3  Key Terms application programming input-process-output primary storage interface (API) (IPO) model protocol arithmetic/logic unit (ALU) interface unit random access memory central processing unit kernel (RAM) (CPU) logical read-only memory (ROM) channel (I/O) memory software communication channel modem standards control unit (CU) network interface card stored program concept distributed computing (NIC) submit (a job) embedded computer open computing suite (protocol) graphical user interface output virtual hardware port (from one computer to von Neumann architecture input another) word Module Code & Module Title Slide Title 4  Introduction to Computer A computer is an electronic device, which accept data and process it and gives us information with set of instructions called program. A computer is a programmable machine, multiuse machine. The word computer is derived from the latin word “computare”. The computer as a system which is a combination of hardware and software joined together.so it has the ability to: 1. Accept data 2. input, store and execute instructions. 3. perform mathematical and logical operation on data. 4. output results. Module Code & Module Title Slide Title 5  Functions of computer There are various function of computer. The main functions are of ve types. They are as follows: 1) Input: The process which enter data inside computer system with the help of input devices is called inputting or In others words the process of entering data and instruction is called input. 2) Processing: The process which performs different mathematical operations and logical operations () is called processing. The computer performs all processing by “calculating,” and “comparing” the data stored in its memory (RAM). It is done in two ways. They are as follows: Mathematical operation The computer can perform any mathematical operation on data by adding, subtracting, multiplying and dividing(+,-,*,/) one set with another. Logical operation The computer can analyze and evaluate data by matching it with sets of known data that are included in the program or called in from storage i.e. it compares two or more data either it is greater than, smaller than, greater or equal to, smaller or equal to and equals to((). Module Code & Module Title Slide Title 6 fi  3. Output: The process of giving information or results after processing and storing is called outputting. It is shown by output devices such as monitor. i.e. The process which display result to the user is called output. 4. Storing The process which helps to store data and information is called storing. The computer is able to store (save) data and programs permanently and retrieve it when required. A system’s size is based on how much disk storage it has. The more disks, the more data are immediately available 5. Controlling The CPU of a computer is responsible for controlling devices attached with computer. i.e. Controlling is the function of controlling all the input and output devices, application programme's and memory units. Module Code & Module Title Slide Title 7  Characteristics of computer All computers have certain common characteristics irrespective their type and size. Computers are not just adding machines; they are capable of doing complex activities and operations. Computers are what they are because of following characteristics. a) Speed: Computers can calculate at very high speeds. As the power of computer increases, the speed also increases. The smallest unit of time in the human experience is realistically the second. We do not think of doing something in less than a second. But a computer performs operations at an incredible speed. It can process information within Pico second. The computers can process data at an extremely fast rate. i.e. in tune of million of instructions per seconds(MIPS). For example A microcomputer can execute a million of instruction per second. b) Storage: A computer can store large amount of data. i.e the storage capacity of computer is high. The data can be stored and retrieved according to the need of the user. In fact it takes very less time to retrieve desired information from a huge amount of data stored inside a computer memory. So the capability of storing and retrieving huge amount of data in fast and ef cient manner is one of the important characteristics of computer. Module Code & Module Title Slide Title 8 fi  c) Accuracy In addition to being fast, computers are very accurate which means that the accuracy of computer is very high. The accuracy of a computer is consistently high and the degree of a accuracy of a computer depends upon its design. Every calculation is performed with the same accuracy. d) Diligence: A computer can perform repetitive task without being bored, tired and losing concentration. It can continuously work for several hours without human intervention after the data and programs are fed to it. They can handle complicated and complex tasks. Diligence means being constant and earnest in effort and application. e)Versatility: Computers are very versatile machines. They can perform activities ranging from simple calculations to complex operations. They can perform different tasks depending upon different programs fed to them. For each task to be performed there is one program associated with it. f) Word length: A digital computer operate on binary digits-0 and 1’s.It can understand information in terms of 0s and 1s.A binary digit is called a bit. A group of 8 bits is called a byte. Thus the number of bits that a computer can process at a time in parallel is called its word length commonly used word length are 8,16,32 or 64 bits. Word length is the measure of the computing power of a computer.The longer word length ,the more powerful the computer is. When we talk about 32-bit computer, it means that its word length is 32 bits. g) Automation: The automation characteristics of a computer is that it nishes any task automatically. computers can be programmed to perform a series of complex tasks involving multiple programs. Module Code & Module Title Slide Title 9 fi  Components of a Computer System Input Unit The Central Processing Unit Output Unit Module Code & Module Title Slide Title 10  1.Input Unit: The input unit consists of input devices that are attached to the computer. These devices take input and convert it into binary language that the computer understands. Some of the common input devices are keyboard, mouse, joystick, scanner etc. The Input Unit is formed by attaching one or more input devices to a computer. A user input data and instructions through input devices such as a keyboard, mouse, etc. The input unit is used to provide data to the processor for further processing. 2. Central Processing Unit: Once the information is entered into the computer by the input device, the processor processes it. The CPU is called the brain of the computer because it is the control centre of the computer. It rst fetches instructions from memory and then interprets them so as to know what is to be done. If required, data is fetched from memory or input device. Thereafter CPU executes or performs the required computation, and then either stores the output or displays it on the output device. The CPU has three main components, which are responsible for different functions: Arithmetic Logic Unit (ALU), Control Unit (CU) and Memory registers. Module Code & Module Title Slide Title 11 fi A. Arithmetic and Logic Unit (ALU): The ALU, as its name suggests performs mathematical calculations and takes logical decisions. Arithmetic calculations include addition, subtraction, multiplication and division. Logical decisions involve the comparison of two data items to see which one is larger or smaller or equal. Arithmetic Logical Unit is the main component of the CPU It is the fundamental building block of the CPU. Arithmetic and Logical Unit is a digital circuit that is used to perform arithmetic and logical operations. B. Control Unit: The Control unit coordinates and controls the data ow in and out of the CPU, and also controls all the operations of ALU, memory registers and also input/output units. It is also responsible for carrying out all the instructions stored in the program. It decodes the fetched instruction, interprets it and sends control signals to input/output devices until the required operation is done properly by ALU and memory. The Control Unit is a component of the central processing unit of a computer that directs the operation of the processor. It instructs the computer’s memory, arithmetic and logic unit, and input and output devices on how to respond to the processor’s instructions. In order to execute the instructions, the components of a computer receive signals from the control unit. It is also called the central nervous system or brain of the computer. Module Code & Module Title Slide Title 12 fl  C. Memory Registers: A register is a temporary unit of memory in the CPU. These are used to store the data, which is directly used by the processor. Registers can be of different sizes(16 bit, 32 bit, 64 bit and so on) and each register inside the CPU has a speci c function, like storing data, storing an instruction, storing address of a location in memory etc. The user registers can be used by an assembly language programmer for storing operands, intermediate results etc. Accumulator (ACC) is the main register in the ALU and contains one of the operands of an operation to be performed in the ALU. Memory Unit is the primary storage of the computer. It stores both data and instructions. Data and instructions are stored permanently in this unit so that they are available whenever required. 3. Output Unit : The output unit consists of output devices that are attached to the computer. It converts the binary data coming from the CPU to human understandable form. The common output devices are monitor, printer, plotter, etc. The output unit displays or prints the processed data in a user-friendly format. The output unit is formed by attaching the output devices of a computer. The output unit accepts the information from the CPU and displays it in a user-readable form. Module Code & Module Title Slide Title 13 fi  What is computer hardware? Computer hardware is a physical device of computers that we can see and touch. For e.g. Monitor, Central Processing Unit, Mouse, Joystick, etc. Using these devices, we can control computer operations like input and output. Computer Hardware Parts ✓ These hardware components are further divided into the following categories, which are: 1. Input Devices 2. Output Devices 3. Storage Devices 4. Internal Components Module Code & Module Title Slide Title 14  1. Input Devices ❖ Input devices are those devices with the help of which the user interacts with the computer. ❖ Or, In other words, with the help of input devices, the user enters the data or information into the computer. ❖ This information or data is accepted by the input devices and converted into a computer- acceptable format, which is further sent to the computer system for processing. ❖ Now we discuss some input devices: Keyboard: ➡ It is the most common and main input device for computers. ➡ The data is inputted by typing on the keyboard. ➡ It consists of 104 keys in total. It contains numeric keys, alphabet keys, and different function keys as well. ➡ Earlier, it was connected to the computer via cable, now as technology has advanced, you can connect a keyboard using Bluetooth. ❖ Mouse: ➡ A mouse is a kind of pointing device which is rolled over to control the cursor on the screen and it has functional keys like left, middle, and right buttons. ➡ Using these functional keys, on by the click of which an object is selected or to open a le by just a click of a mouse. ➡ It also consists of a sensor inside which noti es its speed to the computer and according to which the cursor is moved on the screen. Module Code & Module Title Slide Title 15 fi fi  Scanner: ‣ As the name suggests, it scans images, documents, etc., and converts them into digital form and that can be further edited and used. ‣ It works just like a Xerox machine. Track Ball: ‣ It is a device much like an upside-down mouse. ‣ It does not use much space for movement like a mouse. ‣ As the trackball remains stationary and the user moves the ball in various directions, it affects the screen movements directly. Light Pen: ‣ It is a light-sensitive device and it is touched to the CRT screen where it can detect, a raster on the screen as it passes by and, with the help of this user can draw anything like lines, gures, or any objects. Microphone: ‣ It is a kind of voice input system that can be attached to a computer system to record sounds. ‣ It converts human speech or voice into electrical signals. ‣ This electrical signal is processed by the computer and the word is recognized. Module Code & Module Title Slide Title 16 fi  Optical Character Reader: ‣ It is used to detect alphanumeric characters that are written or printed on paper using a low-frequency light source. ‣ This light is absorbed by the dark areas and re ected by the light areas, now this re ected light is received by the photocells. ‣ It is like a scanner. Bar Code Reader: ‣ It is used to read bar codes and convert them into electric pulse which will further processed by the computer. ‣ Here, the barcode is data that is coded into white and black lines(or light and dark lines). Module Code & Module Title Slide Title 17 fl fl  2. Output Devices ✤ These are the devices that are used to display the output of any task given to the computer in human- readable form. ✤ Now we discuss some output devices: Monitor: ‣ The monitor is the main output device. ‣ It is also called VDU(visual display unit) and it looks like a TV screen. ‣ The Monitor displays the information from the computer. It is used to display text, video, images, etc. Printer: ‣ A printer is an output device that transfers data from the computer in a printed format by using text or images on paper. ‣ There are both colored and black & white printers. ‣ Further, there are also different types of printers, like Laser Printer, Dot-matrix printers, and Inkjet printers. Plotter: ‣ It is similar to a printer but potters are large in size. ‣ A plotter is used to generate large drawings, architectural blueprints, etc. on paper and these are high-quality images and drawings and large in size. Module Code & Module Title Slide Title 18  Speakers: ‣ It is a very common output device and it gives sound as an output. ‣ Speaker is generally used to play music or anything having sound. 3. Storage Devices ✤ There are some devices that are used for storage purposes and are known as secondary storage devices. ✤ Some of them were discussed below: CD (Compact disc): ‣ A CD is circular in shape and made up of thin platted glass and plastic polycarbonate material. ‣ It has a storage capacity of 600 MB to 700 MB of data. ‣ It has a standard size of 12 cm with a hole in the center of about 1.5 cm and 1.2 mm in thickness. ‣ There are basically 3 types of CDs, which are: CD-ROM (CD – Read Only Memory): ‣ Contents of this type of CD cannot be erased by the user. ‣ Only the publisher is allowed to access the data imprinted on this CD. ‣ CD-ROM is basically used for commercial purposes like for a music album or any application package by a software company. Module Code & Module Title Slide Title 19  CD-R (CD-Recordable): ‣ In this, content or data can be stored once. ‣ After that, they can be read many times but the data or content cannot be rewritten or erased. (Kind of one-time use) CD-RW(CD-Rewritable): ‣ As the name suggests, this type of CD is used to rewrite the content or erase previous content and again write new content many times. DVD (Digital Video/Versatile Disc): ‣ A DVD is the same as a CD but with some more features. ‣ A DVD comes in single and dual-layer formats. It has much greater storage capacity in comparison to CD. ‣ The storage capacity of a DVD with one-sided single layer is – 4.7 GB, one-sided double layer – 8.5 GB, double-sided single layer – 9.4 GB, and double-sided double layer – 17 GB. ‣ There are also some types in DVDs, which are : DVD-ROM: ‣ In this type, the contents of the DVD cannot be written on or erased by the user. ‣ DVD ROM is used for applications and database for distributing them in large amounts. DVD-R / DVD+R: ‣ DVD-R (DVD minus R) and DVD+R (DVD plus R) are two different kinds of discs and they are once recordable format. ‣ Also, they have no difference virtually. Module Code & Module Title Slide Title 20  DVD-RW / DVD+RW: ‣ This is a kind of rewritable disc and it allows up to 1,000 rewrites. DVD-RAM: ‣ DVD RAM is accessed like a hard disk. It provides high data security and storage capacity. ‣ This is a kind of rewritable disc and it allows up to 1,00,000 rewrites. Hard Disk: ✤ An hard disk is a non-volatile storage device that uses its read/write heads to store digital data on a magnetic surface of a rigid plate. ✤ It is generally 3.5 inches in size for desktops and 2.5 inches in size for laptops. ✤ A hard disk can be classi ed further into 3 types, which are: Internal Hard Disk: ‣ It has a common storage capacity stated as GB or TB. ‣ A system case or cabinet is the place where it is located. ‣ It can perform faster operations and its storage is xed. It is mainly used to store large data les and programs. Internal Cartridges: ‣ The Internal hard disk can’t be removed from the system cabinet easily. ‣ To resolve this problem Internal Cartridges are introduced. ‣ So, Internal cartridges are easy to remove CDs. ‣ It has a storage capacity of 2 GB to 160 GB. ‣ It is used as an alternative to an internal hard disk. Module Code & Module Title Slide Title 21 fi fi fi  Hard Disk Packs: ‣ It is used by organizations such as banks, and government sector organizations to store large amounts of data. ‣ It has a storage capacity of a range of PB( Peta Bytes). Hardware Components ✤ Some important hardware devices known as the internal components are discussed below: 1. CPU (Central Processing Unit) ‣ The CPU is also known as the heart of the computer. ‣ It consists of three units, generally known as the control unit, Arithmetic Logical Unit (ALU), and the memory unit. ‣ Below is the block diagram of the CPU is given: Module Code & Module Title Slide Title 22 ‣ As shown in the diagram input is given to the CPU through input devices. ‣ This input goes to memory and the control unit gets instructions from memory. ‣ The control unit now decides what to do with the input or instructions and transfers it to ALU. ‣ Now, ALU performs various operations like addition, subtraction, multiplication, division, logical operations, etc. ‣ After that, the nal result gets stored in memory and nally passed to output devices to give the output. ‣ So, this is how the CPU works. 2. Motherboard ‣ It is the main circuit board inside a computer and it contains most of the electronic components together. ‣ All the components of the computer are directly or indirectly connected to the motherboard. ‣ It includes RAM slots, controllers, system chipsets, etc. 3. RAM (Random Access Memory) ‣ It is also known as temporary or volatile memory. ‣ It holds the program and data, which are currently in process or processing. ‣ All the data is erased as soon as the computer is turned off or in case of a power failure. ‣ Data stored in this memory can be changed. ‣ There are two types of RAM:- Module Code & Module Title Slide Title 23 fi fi  1. SRAM (Static RAM): ‣ SRAM basically consists of a ip- op using a transistor or Mosfet (MOS). ‣ It is fast and has less access time. ‣ In this refreshing circuits are not required. ‣ But it is costly and requires more space. ‣ For e.g. cache memory. 2. DRAM (Dynamic RAM): ‣ DRAM consists of capacitors and the data is stored in the form of capacitors. ‣ Capacitors charge when data is 1 and don’t charge if data is 0. ‣ It requires refreshing circuits, as leakage of current in the capacitor can occur, so they need to be refreshed to the data. ‣ It is slower and has a higher access time. ‣ It is cheaper in comparison with SRAM. ‣ For e.g. Main memory. 4. Video Graphics Array Port ‣ A video input commonly used on computer monitors is called a video graphics array (VGA) port. ‣ Verifying that there isn’t a loose connection, a damaged cable, or a broken display is one step in troubleshooting a VGA port. ‣ Compressed air can also be sprayed inside the VGA port by a computer expert to make sure it’s dust-free. Module Code & Module Title Slide Title 24 fl fl 5. Power Supply ‣ All of a computer system’s parts are powered by a power source. ‣ Typically, a power cord is used to connect a computer tower to an electrical outlet. ‣ By turning off the computer, unplugging and separating the power supply cord, or trying a different cord or socket, a technician can diagnose the power supply. 6. Cooling Fan ‣ A computer’s system to prevent overheating uses cooling fans. ‣ To aid customers who use their computers intensively, such as when streaming video or playing games, many computers contain more than one cooling fan. ‣ If a user detects their computer overheating, a computer expert might need to repair the cooling fan. ‣ The blades may be examined for any damage and cleared of any foreign objects. ‣ A technician’s standard method of troubleshooting may involve replacing computer fans. 7. Hard Drive ‣ On a computer system, les, programs, and other types of information are stored on hard drives, which are data storage devices. ‣ They utilise hard drives, which are magnetically coated discs used to store digital versions of information. ‣ A computer technician can suspect a corrupt hard disk when a hard drive dies. Module Code & Module Title Slide Title 25 fi  Central Processing Unit This article aims at explaining the various functions of the central processing unit and its components. De nition: The Central Processing Unit (CPU) is the brain of a computer. It is the part of a computer that performs the instructions of a computer program by performing the basic operations such as addition, subtraction, and operations on data in memory. It interprets and executes instructions from a computer program to perform tasks such as controlling input/output devices, running applications, and handling data. A CPU consists of two parts: – The Control Unit directs and manages operation sequences. – The Arithmetic Logic Unit carries out arithmetic and logical operations. A CPU comprises four components: a control unit, an arithmetic logic unit, registers, and memory. The control unit tells the other parts how to perform operations. The arithmetic logic unit performs mathematical operations on data in the registers. The registers hold data that needs to be processed by the CPU while working on the ALU. Memory stores programs and data to be accessed quickly by the CPU. Module Code & Module Title Slide Title 26 fi 1. Control unit (CU): Control units control how a computer’s input and output devices, arithmetic and logical units, and memory respond to instructions sent to the CPU. It takes the input, converts it to a decoded format, and then sends it to the computer’s processor for processing, where it performs the desired operation. There are two types of control units: hard-wired CU and micro-programmable CU. Function: It controls the order in which instructions enter and leave the processor and how the instructions are executed It is responsible for taking the input, converting it into a signal, and storing it for further processing It controls the functionality of other CPU components, such as ALUs and registers 2. Arithmetic Logic Unit (ALU): Arithmetic logic units are responsible for arithmetic logic calculations and decisions in the system. This is also known as the mathematical brain of a computer. The ALU uses registers for calculations. It takes input from an input register, operates on the data, and stores the output in an output register. Module Code & Module Title Slide Title 27 Function: This is mainly used to make decisions Performs arithmetic and logical operations It acts as a bridge between your computer’s primary and secondary storage. All information exchanged between primary and secondary storage goes through the ALU 3. Register: Registers are part of the computer’s memory and temporarily store instructions to provide instructions to the processor when needed. These registers are also called processor registers because they play an essential role in processing data. These registers store data in the form of a memory address and, after processing the instruction that exists at that memory address, store the memory address of the next instruction. Different types of registers perform different functions. Module Code & Module Title Slide Title 28 Function: Input registers are used to transfer inputs The output register is used to transfer the output Temporary registers store data temporarily The address register stores the address in memory The program counter stores the address of the instruction Data registers hold memory operands The command register contains the command code 4. Cache : A cache is a random access memory that temporarily stores a small amount of data and instructions that can be reused when needed. Instructions can be fetched directly from the cache quickly instead of fetching them from RAM, reducing the time it takes to fetch instructions. Functions: These reduce the time it takes to fetch and execute statements Temporarily save the data for later use Module Code & Module Title Slide Title 29 5. Bus: Buses are connections between various components of a computer system and processors. These are used to send signals and data from the processor to various devices and vice versa. There are three types of buses. Functions: Processes use the address bus to send memory addresses to other components The processor uses the data bus to send the actual data to the component, and the processor uses the control bus to send control signals to other devices Used to exchange data between different devices Powers various components of the system Module Code & Module Title Slide Title 30  Computer Memory Computer memory is just like the human brain. It is used to store data/information and instructions. It is a data storage unit or a data storage device where data is to be processed and instructions required for processing are stored. A modern digital computer represents data using the binary numeral system. Text, numbers, pictures, audio, and nearly any other form of information can be converted into a string of bits, or binary digits, each of which has a value of 1 or 0. The most common unit of storage is the byte, equal to 8 bits. Types of Computer Memory: – In general, computer memory is of three types: 1.1. Primary memory 2.2. Secondary memory 3.3. Cache memory Module Code & Module Title Slide Title 31 The primary functions of RAM: - It stores data or program and other information those can be quickly accessed by the CPU at the time of execution at consistent rate. - It stores the copy of main software program that controls the general operations of the computer. - This copy is loaded into the main memory when the computer power is on. - It stores data that has been input from keyboard or other input devices until instruction call for the data to be transferred into the CPU for processing. Types of RAM: 1. SRAM(static Random Access memory): - The word “static” indicates that the memory retains its contents as long as power remains applied, - unlike dynamic RAM (DRAM) that needs to be periodically refreshed whereas - SRAM do not need to refresh(ie recharging the memory circuit chips)and - SRAM is a little more expensive, but faster more reliable than DRAM. - SRAM is also easier to control. Module Code & Module Title Slide Title 32 2.DRAM(Dynamic Random Access Memory): - DRAM are slower ,cheaper and popular than SRAM. - DRAM is called dynamic because it must constantly be refreshed or it will lose the data which it is supposed to be storing. - Refreshing DRAM consists of reading the contents from the DRAM and immediately writing them back to the DRAM. Types of DRAM: A) SDRAM(Synchronous DRAM): - Synchronous dynamic random access memory (SDRAM) is dynamic random access memory (DRAM) that has a synchronous interface which means it is directly depend on the clock speed of the entire system. - The SDRAM can handle higher bus speed. - The SDRAM is faster than DRAM ie the SDRAM could operate at up to 100MHz. Module Code & Module Title Slide Title 33 B) RDRAM(Rambus DRAM): - Stands for “Rambus Dynamic Random Access Memory.” - It is a type of RAM made by Rambus and is the fastest type of computer memory available. - Typical SDRAM can transfer data at speeds up to 133 MHz, while standard RDRAM can crank it up over 1 GHz. - Though some motherboards can use RDRAM as system memory, it is so fast, most boards cannot fully bene t from the speed. - Because of this, RDRAM is typically used for video memory on graphics acclerator cards, for cache memory (located on the CPU), and for system memory in high- performance workstations and servers. C) VRAM(video-DRAM): - It is another types of DRAM that is used in PC’S to handle graphical data and display images on the screen. it is called display or graphic memory. - This memory chips is mounted on display cards,quite fast,as it needs to respond quickly to the CPU’s instructions and constantly refresh and update the screen image so that there is no icker. Module Code & Module Title Slide Title 34 fl fi 2. ROM(Read Only Memory): - NVM or non-volatile storage, is computer memory that can retain the stored information even when not powered. - Examples of non-volatile memory include read-only memory, ash memory, most types of magnetic computer storage devices (e.g. hard disks, oppy disk drives, and magnetic tape), optical disc drives. - Non-volatile memory is typically used for the task of secondary storage, or long-term persistent storage. - The ROM that type of memory chip which store data that only can be Read only. - That is the data stored in ROM can not be modi ed hence named Read only. - Thus ROM consists of data and set of program instruction to load the computer system when you rst turned on the computer. - These sequence of instructions are stored permanently in ROM chips often by chip manufacturing company which is called rmware. - Note: most of digital devices such as calculators, mobile, laser printer uses ROM. Module Code & Module Title Slide Title 35 fi fi fi fl fl Types of ROM: 1.PROM(Programmable Read only memory): - A PROM is a blank memory chip on which data can be written only once and and can be read many times but can not changed data. - Once the program has been written onto PROM ,it remains there permanently. - The difference between ROM and PROM is that ROM is programmed during the manufacturing process where PROM is manufactured as a blank memory. - To write data on PROM you need special components PROM burner. - The process of programming a PROM is called burning the PROM. 2.EPROM(Erasable Programmable Read only memory): - EPROM chips are developed as an improvements over PROM chips. - It works as PROM except that data written can be erased. - So to erase data it uses special ultraviolet light and then new data can be written. - To change instruction on EPROM chip, the chip must be taken out from the machine. - In EPROM we can not make changes in the data individually that have already written. - To write new data or delete existing data, we have to erase all the data from the EEPROM. Module Code & Module Title Slide Title 36 3. EEPROM(Electrically Erasable Read-only memory): - EEPROM chip avoids the inconvenience of having to take out chips out of the computer to change data and instructions. - Instead changes are made under software control. - Unlike EPROM we can make changes to the existing data without erasing the entire data.EEPROM requires data written and erased one bit at a time. - But EEPROM are expensive than other ROM. 4. Flash Memory: - Flash Memory is special type of EEPROM that can be programmed and erased in blocks instead of one bit at a time. - These memories are popular in world which are commonly used in pen drives,Digital cameras, mobile phones etc. - The modern PC uses ash memory to store instructions so that which makes easily to update. - Flash memory gets its name because the microchip is organized so that a section of memory cells are erased in a single action or “ ash.” - Flash memory is non-volatile computer memory that can be electrically erased and reprogrammed. Module Code & Module Title Slide Title 37 fl fl  2. Secondary memory (Auxiliary memory): - Secondary memory is where programs and data are kept on a long-term basis. Common secondary storage devices are the hard disk and oppy disks. - Secondary memory (or secondary storage) is the slowest and cheapest form of memory. It cannot be processed directly by the CPU. - It must rst be copied into primary storage(also known as RAM ). - Secondary memory devices include magnetic disks like hard drives and oppy disks; optical disks such as CDs and CDROMs ; and magnetic tapes, which were the rst forms of secondary memory. Types of Secondary Memory: A) Magnetic Tape: - Magnetic tape is the most popular storage medium for large data, which are sequentially accessed and processed. - The magnetic tape medium is a plastic ribbon, which is ½” or ¼” wide and 50 to 2400 feet long. - It is coated with a magnetically recording material, such as iron oxide. - This type of device is still used for large data backup because these are cheaper than other devices. Module Code & Module Title Slide Title 38 fi fi fl fl - Like audio or videotape, the magnetic tape used in computer system which can also erased and reused inde nitely. - Old data on a tape are automatically erased ,as new data are recorded in the same area. - Tapes for computer are similar to the tapes used to store music. - Accessing data on tapes however is much slower than accessing data on disk. B) Magnetic Disk: - Magnetic disk is a circular disk which is coated with magnetic material. - The disk rotates with very high speed inside the computer drive. - Data is stored on both the surface of the disk. magnetic disks are most popular for direct access storage device. - Each disk consists of a number of indivisible concentric circles called tracks. - Information recorded on tracks of a disk surface in the form of magnetic spots. - A good example of magnetic disks is hard disk. Module Code & Module Title Slide Title 39 fi  Hard Disk: - The hard disk is direct-access storage medium with a rigid magnetic disk. - The disk is divided into number of tracks and each tracks are divided into sectors. - A hard disk uses round, at disks called platters, coated on both sides with a special media material designed to store information in the form of magnetic patterns. - The platters are mounted by cutting a hole in the center and stacking them onto a spindle. - The platters are rotated at very high speed, driven by a special spindle motor connected to the spindle. - Each platters consists of READ/WRITE head to read and write data. - The disks are rotated at very high speed (usually around 7200RPM-revolution per minute.) Floppy Disk: - Floppy disk is a round, at piece of exible plastic coated with magnetic oxide. - These are small removal, media storage device. - The data is recorded on thin plastic lm. - Floppy disk is a soft magnetic disk and it is a thin piece of exible plastic called oppy disk, or also called oppy Diskette. - They are removable disks. Module Code & Module Title Slide Title 40 fl fl fl fl fl fi fl - A oppy disk is inserted inside the computer the oppy drive when needed. - These are different sizes of oppy disk 5.25” or 3.5” having capacity 1.2MB and 1,44MB respectively. C) Optical Disk: - An optical disk is random access storage medium. It is made up glass. - Optical disks uses light technology where laser beam is projected and re ected light is observed. - The As compared to magnetic tape and disk, optical disk is relatively new secondary storage medium. - An optical disk storage system consists of a rotating disk which is coated with a thin metal or some material that is highly re ective. - This type of disk uses laser beam technology for READ/WRITE data. - Due to the use of laser beam technology, optical disks are also known as laser disk or optical laser disks. - Unlike magnetic disks, which have several concentric tracks, an optical disk has one long track, which starts at the outer edge and spirals inwards to the center. - The optical disk has no mechanical R/W arm movements. Module Code & Module Title Slide Title 41 fl fl fl fl fl Types of optical disks: 1. CD-ROM(compact-disk read only memory): - It is a music CD technology and works much like the music CD’S used in music system. - The CD-ROM disk is a shiny, silver color metal disk. - It has storage capacity of about 650MB or more and it is a read only storage medium such that can not be modi ed. 2. CD-RW(compact disk read/write): - CD-RW is a CD-Rewritable disc and this is new type of CD disc that enables us to write onto it in multiple session. - Thus we can treat the optical disk just like oppy disk or hard disk writing onto multiple times. 3. DVD( Digital versatile Disc): - It is family of optical discs that are the same overall dimension of a CD, but have signi cantly higher capacity. - DVD’s are double sided, whereas CD’s are single sided. it needs DVD drive and its capacity ranges from 4.5gb to 17GB. Module Code & Module Title Slide Title 42 fi fi fl  Software Components Software components are essential building blocks that enable computers to function effectively. Each component has a unique role, ensuring smooth operation and user interaction. Let’s explore these components in more depth: 1. Applications: - Applications, or software applications, are programs that help users perform speci c tasks on a computer. - Common examples include web browsers, word processors, video games, and email clients. - Applications are designed to solve real-world problems or ful ll user needs. - For instance, Microsoft Word is used for document creation, while Google Chrome is for browsing the internet. Module Code & Module Title Slide Title 43 fi fi User interaction: - Users interact directly with applications to perform tasks like writing, playing games, or designing graphics. Types of applications: - Applications can be desktop-based (like MS Word) or web-based (like Google Docs). - Mobile apps also fall under this category. Module Code & Module Title Slide Title 44 2. Operating System (OS): - The operating system (OS) is a critical software layer that manages hardware and software resources. - It serves as an intermediary between users and computer hardware, ensuring that applications can run smoothly. Key functions: ◦ Hardware management: The OS controls devices like printers, disk drives, and keyboards. ◦ Application management: It ensures that multiple applications can run simultaneously without interfering with each other. ◦ User interface: Modern OSs, like Windows or macOS, offer graphical user interfaces (GUIs) that make it easy for users to interact with the system. Module Code & Module Title Slide Title 45 3. API (Application Programming Interface): - APIs are a set of rules or protocols that allow different software programs to communicate and share data. - They de ne how software components should interact with each other. ◦ Example: When you use a weather app, it connects to an API that fetches data from a remote server to display weather updates. ◦ Usage in software development: Developers use APIs to integrate third-party services, like payment gateways or social media logins, into their applications without having to build everything from scratch. Module Code & Module Title Slide Title 46 fi  4. File Management: - File management refers to how data is stored, organized, and retrieved on a computer system. - The OS provides the le system to manage these les. - ◦ File hierarchy: Files are typically organized in a hierarchical structure of directories (folders) and subdirectories. ◦ Operations: Users can create, edit, save, delete, move, or rename les. For example, you might store a project document in a folder and retrieve it later when needed. ◦ Security: File management systems often include permissions to control access, ensuring that sensitive data is protected. 5. Input/Output (I/O) Management: - I/O management is the part of the OS that handles communication between the computer and external devices. - Input devices include keyboards, mice, and microphones, while output devices include monitors, printers, and speakers. Module Code & Module Title Slide Title 47 fi fi fi  ‣ Input operations: The system captures user input from devices (e.g., typing on a keyboard or clicking a mouse). ‣ Output operations: It sends data to output devices, like displaying an image on a screen or printing a document. ‣ I/O buffering: The OS often uses buffers to temporarily store data between input and output operations, improving performance. 6. Kernel: - The kernel is the heart of the operating system. - It is the core component that directly interacts with the hardware. - The kernel ensures that all system resources, such as CPU, memory, and storage, are properly allocated to various applications. Types of kernels: ◦ Monolithic kernels: These include all necessary services in one large program. ◦ Microkernels: These break the OS into smaller, more manageable parts. Key tasks: ๏ Process management: The kernel schedules and manages processes (programs running on the computer). Module Code & Module Title Slide Title 48 Hardware control: It interacts with the hardware, ensuring ef cient communication between hardware devices and software. 7. Memory Management: - Memory management ensures that each application running on the computer has enough memory (RAM) to function correctly. - It controls how the system’s memory is allocated and deallocated to processes. Virtual memory: To maximize performance, the OS may use virtual memory, where parts of programs that aren’t currently in use are stored temporarily on the hard disk, freeing up RAM. Memory allocation: When a program starts, the OS allocates a certain amount of memory for it. Once the program ends, that memory is freed up for other applications. Module Code & Module Title Slide Title 49 fi 8. Resource Scheduling: - Resource scheduling is the process of allocating system resources (like CPU time, memory, or disk space) to various tasks based on priority and requirements. CPU scheduling: The OS uses algorithms to decide which tasks should get the CPU’s attention rst, ensuring high-priority tasks are completed quickly. Time-sharing: In modern computers, resource scheduling ensures that multiple users and processes can share system resources ef ciently, allowing for multitasking and high productivity. 9. Program Communication (Inter-process Communication, or IPC): - When multiple programs or processes need to work together, they communicate using inter-process communication (IPC) mechanisms. - This can involve: Shared memory: Multiple processes access the same memory space to exchange information. Message passing: Programs send messages to one another to share data or signal that a task has been completed. Use case: In an email system, different processes (like the email client and server) need to communicate to ensure that emails are sent and received correctly. Module Code & Module Title Slide Title 50 fi fi 10. Security: - Security is one of the most important aspects of any software system. - It ensures that the system is protected from unauthorized access, viruses, malware, and data breaches. Authentication: Security systems verify the identity of users trying to access the system (e.g., using passwords or biometric scans). Authorization: Once authenticated, users are given access to speci c resources based on their roles and privileges. Data protection: Encryption methods are used to keep sensitive data secure, whether it’s stored on the system or transmitted over a network. 11. Network Module: - The network module is responsible for handling all communication between the computer and external networks. - This includes managing data transmission over the internet, local area networks (LAN), and other communication protocols. Network communication: The network module ensures that data is sent and received correctly across networks. This includes handling errors, packet loss, and data collisions. Module Code & Module Title Slide Title 51 fi  Internet access: When you use a browser to load a webpage, the network module is responsible for establishing the connection to the server and fetching the required data. Module Code & Module Title Slide Title 52  Communication Components Hardware Communication Components: 1. Communication Channels: - Communication channels are the mediums that carry data between different devices in a network. - These channels can be wired or wireless, and they are essential for data transmission. ◦ Wired Communication Channels: ▪ Wire Cable: Traditional copper cables (such as Ethernet cables) that transmit data in electrical signals. ▪ Phone Lines: Used for voice communication and low-speed data transmission, commonly through the Public Switched Telephone Network (PSTN). ▪ Fiber Optic Cable: High-speed transmission medium that uses light signals to transmit data over long distances with minimal loss and interference. Module Code & Module Title Slide Title 53  ◦ Wireless Communication Channels:: ▪ Infrared Light: Uses infrared waves for short-range communication, often found in devices like remote controls. ▪ Radio Waves: Wireless signals used for communication in technologies such as Wi-Fi, Bluetooth, and mobile networks. Radio waves can cover long distances, allowing for wide-area communication. 2.Interface Hardware: - Interface hardware connects the computer system to communication channels and manages data transmission between devices. - It ensures that the computer can send and receive data over a network. Modem (Modulator-Demodulator): Converts digital signals from a computer into analog signals for transmission over telephone lines and vice versa. Common in older systems for internet access via dial-up. Network Interface Card (NIC): A hardware component that allows computers to connect to a network. NICs may be wired (Ethernet) or wireless (Wi-Fi). They convert data from the computer into a form that can be transmitted over a communication channel. Module Code & Module Title Slide Title 54 Software Communication Components: 1. Establish Connections: ➡Protocol Suites: Software protocols (such as TCP/IP) manage communication and ensure proper data transfer between computers over a network. ➡TCP (Transmission Control Protocol): Ensures reliable data transmission by establishing a connection, controlling data ow, and managing packet loss. ➡IP (Internet Protocol): Responsible for addressing and routing packets of data to ensure they reach their destination. ➡Connection Setup: Software establishes a session or connection between devices, ensuring they can communicate effectively (e.g., HTTP requests in web browsers). 2. Control Flow of Data: ➡ Flow control ensures that data is transmitted at a rate that both sending and receiving devices can handle, preventing data loss or system overload. ➡ Buffering Mechanisms: Manage data ow between fast and slow devices. Buffers store data temporarily until the receiving device is ready to process it. ➡ Windowing Protocols: Control how much data can be sent before receiving an acknowledgment from the other device (e.g., TCP uses windowing for ow control). Module Code & Module Title Slide Title 55 fl fl fl  3. Directs Data to Applications: ➡ Once the data is transmitted, it needs to be directed to the proper application on the receiving computer for use. ➡ Routing Protocols: Software that directs data through the network to ensure it reaches the correct destination. Examples include RIP (Routing Information Protocol) and OSPF (Open Shortest Path First). ➡ Network Address Translation (NAT): A technique used by routers to direct incoming and outgoing traf c to the correct devices in a private network. Module Code & Module Title Slide Title 56 fi  Types of Computer ✴ We can categorize computer in two ways: on the basis of data handling capabilities and size. On the basis of data handling capabilities, the computer is of three types: Analogue Computer Digital computer Hybrid Computer 1. Analog Computer: - Analog Computers are particularly designed to process analog data. - Continuous data that changes continuously and cannot have discrete values are called analog data. - So, an analog computer is used where we don’t need exact values or need approximate values such as speed, temperature, pressure, etc. - It can directly accept the data from the measuring device without rst converting it into numbers and codes. - It measures the continuous changes in physical quantity. - It gives output as a reading on a dial or scale. For example speedometer, mercury thermometer, etc. Module Code & Module Title Slide Title 57 fi  2. Digital Computer: - Digital Computers are designed in such a way that they can easily perform calculations and logical operations at high speed. - It takes raw data as input and processes it with programs stored in its memory to produce the nal output. - It only understands the binary input 0 and 1, so the raw input data is converted to 0 and 1 by the computer and then it is processed by the computer to produce the result or nal output. - All modern computers, like laptops, desktops including smartphones are digital computers. 3. Hybrid Computer: - As the name suggests hybrid, which means made by combining two different things. - Similarly, the hybrid computer is a combination of both analog and digital computers. - Hybrid computers are fast like analog computers and have memory and accuracy like digital computers. - So, it has the ability to process both continuous and discrete data. Module Code & Module Title Slide Title 58 fi fi  - For working when it accepts analog signals as input then it converts them into digital form before processing the input data. - So, it is widely used in specialized applications where both analog and digital data are required to be processed. - A processor which is used in petrol pumps that converts the measurements of fuel ow into quantity and price is an example of a hybrid computer. On the basis of size, the computer can be of ve types: ‣ Super Computer ‣ Mainframe Computer ‣ Mini Computer ‣ Workstation Computer ‣ Personal Computer (PC) Module Code & Module Title Slide Title 59 fi fl  1. Supercomputer: - When we talk about speed, then the rst name that comes to mind when thinking of computers is supercomputers. - They are the biggest and fastest computers (in terms of speed of processing data). - Supercomputers are designed such that they can process a huge amount of data, like processing trillions of instructions or data just in a second. - This is because of the thousands of interconnected processors in supercomputers. - It is basically used in scienti c and engineering applications such as weather forecasting, scienti c simulations, and nuclear energy research. - It was rst developed by Roger Cray in 1976. Module Code & Module Title Slide Title 60 fi fi fi fi  2. Mainframe computer: - Mainframe Computers are designed in such a way that they can support hundreds or thousands of users at the same time. - It also supports multiple programs simultaneously. - So, they can execute different processes simultaneously. - All these features make the mainframe computer ideal for big organizations like banking, telecom sectors, etc., which process a high volume of data in general. 3. Minicomputer: - Minicomputer is a medium size multiprocessing computer. - In this type of computer, there are two or more processors, and it supports 4 to 200 users at one time. - Minicomputer is similar to Microcontroller. - Minicomputers are used in places like institutes or departments for different work like billing, accounting, inventory management, etc. - It is smaller than a mainframe computer but larger in comparison to the microcomputer. Module Code & Module Title Slide Title 61 4. Workstation Computer: - A workstation computer is designed for technical or scienti c applications. - It consists of a fast microprocessor, with a large amount of RAM and a high-speed graphic adapter. It is a single-user computer. - It is generally used to perform a speci c task with great accuracy. 5. Personal Computer (PC): - Personal Computers is also known as a microcomputer. - It is basically a general-purpose computer designed for individual use. - It consists of a microprocessor as a central processing unit(CPU), memory, input unit, and output unit. - This kind of computer is suitable for personal work such as making an assignment, watching a movie, or at the of ce for of ce work, etc. - For example, Laptops and desktop computers. Module Code & Module Title Slide Title 62 fi fi fi fi  Virtualization ✴ Virtualization is the creation of a virtual version of an actual piece of technology, such as an operating system (OS), a server, a storage device or a network resource. - Virtual software mimics the functions of physical hardware to run multiple virtual machines simultaneously on a single physical machine. - Businesses use virtualization to use their hardware resources ef ciently and get greater returns from their investment. - It also powers cloud computing services that help organizations manage infrastructure more ef ciently. Why is virtualization important? - By using virtualization, you can interact with any hardware resource with greater exibility. - Physical servers consume electricity, take up storage space, and need maintenance. - You are often limited by physical proximity and network design if you want to access them. - Virtualization removes all these limitations by abstracting physical hardware functionality into software. - You can manage, maintain, and use your hardware infrastructure like an application on the web. Module Code & Module Title Slide Title 63 fl fi fi  Virtualization example: Consider a company that needs servers for three functions: 1. Store business email securely 2. Run a customer-facing application 3. Run internal business applications Each of these functions has different con guration requirements: The email application requires more storage capacity and a Windows operating system. The customer-facing application requires a Linux operating system and high processing power to handle large volumes of website traf c. The internal business application requires iOS and more internal memory (RAM). - To meet these requirements, the company sets up three different dedicated physical servers for each application. - The company must make a high initial investment and perform ongoing maintenance and upgrades for one machine at a time. - The company also cannot optimize its computing capacity. - It pays 100% of the servers’ maintenance costs but uses only a fraction of their storage and processing capacities. Module Code & Module Title Slide Title 64 fi fi  Ef cient hardware use: - With virtualization, the company creates three digital servers, or virtual machines, on a single physical server. - It speci es the operating system requirements for the virtual machines and can use them like the physical servers. - However, the company now has less hardware and fewer related expenses. Infrastructure as a service: - The company can go one step further and use a cloud instance or virtual machine from a cloud computing provider such as AWS. - AWS manages all the underlying hardware, and the company can request server resources with varying con gurations. - All the applications run on these virtual servers without the users noticing any difference. - Server management also becomes easier for the company’s IT team. Module Code & Module Title Slide Title 65 fi fi fi  Examples: There are six areas of IT where virtualization is frequently used: - Network virtualization combines the available resources in a network by splitting up the available bandwidth into connectivity channels, each of which runs independently from the others. - With virtual network, each channel can be assigned or reassigned to a particular server or device in real time. - Much like a partitioned hard drive, virtualization separates the network into manageable parts, disguising the true complexity of the network. - Storage virtualization pools physical storage from multiple network storage devices into a centrally managed console. - Storage virtualization is commonly used in storage area networks. - Server virtualization hides server resources, including the number and identity of individual physical servers, CPUs and OSes, from users. - Virtual servers spare users from having to manage the complicated details of server resources. - They also increase server, processor and OS sharing as well as resource use and expansion capacity. Module Code & Module Title Slide Title 66  - Data virtualization abstracts the technical details of data and data management, such as location, performance and format. - Instead, data virtualization focuses on broader access and resiliency. - Desktop virtualization virtualizes a workstation load rather than a server. - This lets the user access a desktop remotely, typically using a thin client at the desk. - With virtual desktop infrastructure, the workstation essentially runs in a data center server and access is more secure and portable. - However, the OS license and infrastructure still must be accounted for. - Application virtualization abstracts the application layer away from the OS. - This lets the application run in an encapsulated form without dependence on the underlying OS. - Application virtualization enables a Windows application to run on Linux and vice versa, and it adds a level of isolation. Module Code & Module Title Slide Title 67  Protocols: Key Communication Rules - Protocols are common ground rules that de ne how computers, I/O devices, and software programs communicate. - They ensure data is transmitted, received, and interpreted consistently and include rules for error checking, data format, and speed. Examples include HTTP (for web communication), FTP (for le transfer), and TCP/IP (for network communication). HTTP (Hypertext Transfer Protocol): - HTTP (Hypertext Transfer Protocol) is a protocol used for transmitting hypertext (such as HTML documents) over the internet. - It is the foundation of data communication for the World Wide Web and operates at the application layer of the Internet Protocol Suite. - Example in Real Life: When you enter https://www.example.com in your browser: 1. Your browser (the client) sends a GET request to the server hosting example.com. 2. The server responds with the HTML content for that page. 3. The browser displays the HTML in a user-friendly format, rendering the web page. Module Code & Module Title Slide Title 68 fi fi  TCP/IP (Transmission Control Protocol/Internet Protocol): - TCP/IP (Transmission Control Protocol/Internet Protocol) is the fundamental communication protocol suite for the internet. - It governs how data is packaged, transmitted, and received between devices across networks. - Real-Life Example: - Imagine sending a package through a courier service: TCP is like a shipping company that breaks the package into smaller, manageable boxes, delivers them reliably, and ensures they arrive in the correct order. IP is like the address system that guides each box to the right destination using the recipient’s unique address (IP address). So, when you stream a video, TCP/IP ensures that the video data packets are delivered reliably, and in the correct order, allowing for smooth playback. SATA (Serial Advanced Technology Attachment): - SATA (Serial Advanced Technology Attachment) is a protocol used to connect storage devices, like hard drives (HDDs) and solid-state drives (SSDs), to a computer’s motherboard. - It enables fast data transfer between the computer and the storage device. Module Code & Module Title Slide Title 69  Real-Life Example: - When you save a large le on your computer, the data is sent from the system’s memory to the storage device (HDD or SSD) via the SATA interface. - SATA ensures this transfer happens quickly and reliably, allowing you to store and access your les ef ciently. - In modern laptops and desktops, the internal drives are commonly connected using SATA. XML (eXtensible Markup Language): - XML (eXtensible Markup Language) is a exible text-based format used to structure and store data in a human-readable and machine-readable way. - It allows users to de ne custom tags to represent different types of data. Real-Life Example: - Imagine an online store that needs to send product data from its inventory system to its website: - - Smartphone - 499.99 - 150 - Module Code & Module Title Slide Title 70 fi fi fi fi fl  - This XML document describes a product with its name, price, and stock count. - The website can read this XML data to display product information dynamically. - XML is commonly used in web services (like APIs), con guration les, and data interchange between applications. RSS (Really Simple Syndication): - RSS (Really Simple Syndication) is a protocol used to distribute and update content from websites in a standardized format. - It allows users to subscribe to updates (like news, blogs, podcasts) and receive them automatically through an RSS feed reader. - Real-Life Example: - If you follow a tech blog, you can subscribe to its RSS feed using a feed reader (like Feedly). - Whenever the blog posts a new article, it will automatically appear in your reader, saving you the time of checking the website manually. - This makes RSS useful for staying up to date on multiple websites, podcasts, or news sources without individually visiting each one. Module Code & Module Title Slide Title 71 fi fi  SIP (Session Initiation Protocol): - SIP (Session Initiation Protocol) is a communication protocol used for initiating, maintaining, and terminating real-time sessions that involve video, voice, and messaging applications. - It is widely used in Voice over IP (VoIP) and multimedia communication. - Real-Life Example: When you make a voice call using a VoIP service (like Skype or Zoom): 1. SIP sends a request to initiate the call, specifying the participants and the type of media. 2. Once the call is accepted, SIP manages the communication session, allowing both parties to talk and share video. 3. When one party hangs up, SIP terminates the session, freeing up resources. In this way, SIP is essential for enabling and managing voice and video calls over the internet. Module Code & Module Title Slide Title 72  Computer Standards: Universal Guidelines for Compatibility De nition: - A standard is a formal document that speci es agreed-upon methods, criteria, or speci cations for processes, products, or services. - It serves to ensure universal compatibility of data formats and protocols, facilitating communication and interoperability between different systems and technologies. - Standards can be created by of cial committees, such as ISO or IEEE, which develop and maintain them through a structured process. - Alternatively, some standards emerge as de facto standards through popular use, becoming widely accepted without formal establishment. - By promoting consistency and quality, standards play a crucial role in enhancing safety, ef ciency, and trust across various industries. Key Examples of Computer Standards: Computer Languages: ◦ Java, SQL, C, JavaScript: Universal programming languages ensuring compatibility across different systems and platforms. Display Standards: ◦ Postscript, MPEG-2, JPEG, GIF: Common formats for rendering text, images, and videos on screens and printers. Module Code & Module Title Slide Title 73 fi fi fi fi fi  Character Set Standards: ◦ ASCII, Unicode, EBCDIC: De nes how text characters are encoded and represented in computers for universal readability. Multimedia Standards: ◦ MPEG-2, MPEG-4, DivX, MP3: Industry standards for encoding and compressing audio and video les for playback across devices. These standards ensure smooth interaction across technologies, making sure everything communicates ef ciently and consistently. Module Code & Module Title Slide Title 74 fi fi fi  A Brief History Of Computers Ancient Times: - Early Man relied on counting on his ngers and toes (which by the way, is the basis for our base 10 numbering system). - He also used sticks and stones as markers. - Later notched sticks and knotted cords were used for counting. - Finally came symbols written on hides, parchment, and later paper. - Man invents the concept of number, then invents devices to help keep up with the numbers of his possessions Module Code & Module Title Slide Title 75 fi  Roman Empire: - The Roman Empire was known for many innovations, including the development of the abacus, which was one of the earliest calculating tools. - Key Points about the Roman Abacus: - The Roman abacus was a simple device used for performing calculations. - It consists of a rectangular frame with grooves or wires where small counters (or beads) could be moved. - The abacus has two main grooves: - Lower Groove: Each counter here represents a value of 1 multiplied by 10^n (where n indicates the position of the counter, similar to place value in our number system). - Upper Groove: Each counter in this groove represents a value of 5 multiplied by 10^n. - This design made it easier for Romans to perform addition, subtraction, and other calculations quickly and accurately. Module Code & Module Title Slide Title 76  Industrial Age - 1600: - During the Industrial Age around the year 1600, a Scottish nobleman named John Napier made signi cant contributions to mathematics while exploring ways to make calculations easier. - Key Contributions of John Napier: - Napier was particularly interested in logarithms, which are a way to simplify complex calculations like multiplication and division. - To help with calculations, he created a set of wooden rods that had logarithmic measurements inscribed on them. - By aligning these rods, he could quickly nd the product or quotient of numbers without doing the actual calculations manually. - These rods became known as Napier’s Bones. - They were an early tool that helped people perform mathematical operations more ef ciently, marking an important advancement in computation during that time. Module Code & Module Title Slide Title 77 fi fi fi  1621 - The Sliderule: - In 1621, William Oughtred from England invented the slide rule, building on John Napier's invention of logarithms and Edmund Gunter's logarithmic scales. - Oughtred inscribed logarithms on strips of wood, creating a calculating tool that was widely used until the mid-1970s, when handheld calculators and microcomputers came into use. - The slide rule was a signi cant advancement in computation for centuries! Module Code & Module Title Slide Title 78 fi  1642 - Blaise Pascal(1623-1662): - At the age of 19, Blaise Pascal, a French mathematician, invented the Pascaline, one of the rst mechanical calculators, to help his father with calculations. - The machine used gears with 10 teeth to perform addition and subtraction, with each turn of a gear triggering the next. - This design became the basis for mechanical calculators used for centuries. - Pascal's work in mathematics and his invention left a lasting legacy, leading to the Pascal programming language being named in his honor. Module Code & Module Title Slide Title 79 fi  1673 - Gottfried Wilhelm von Leibniz (1646-1716): - Gottfried Wilhelm von Leibniz independently developed calculus alongside Isaac Newton. - He also invented the Leibniz Wheel, a calculating machine that could add, subtract, multiply, and divide, improving on Pascal’s design. - Leibniz’s machine used repeated addition and subtraction, much like later mechanical calculators. - He also introduced binary arithmetic, a key concept in modern computers. Module Code & Module Title Slide Title 80  1725 - The Bouchon Loom: - Basile Bouchon, the son of an organ maker, worked in the textile industry where intricate fabric patterns were popular. - To simplify complex weaving, he adapted the punched paper rolls his father used for player organs to control looms. - The holes in the paper lifted speci c threads, allowing the pattern to be woven repeatedly. - This was the rst instance of a stored program using punched paper. - However, the paper would tear easily and was dif cult to advance, so Bouchon’s invention didn’t gain much popularity and was eventually abandoned. Module Code & Module Title Slide Title 81 fi fi fi  1728 - Falçon Loom: - 1728, Jean-Baptiste Falcon improved Bouchon’s loom by using durable punched cardboard cards instead of paper rolls. - However, the cards often got shuf ed, and switching them was tedious. - As a result, Falcon's loom, like Bouchon's, was eventually abandoned. Module Code & Module Title Slide Title 82 fl  1745 - Joseph Marie Jacquard (1752-1834): - Joseph M. Jacquard combined Bouchon’s punched roll and Falcon’s durable punched cards to create a fully functional programmable loom. - By linking punched cards into a continuous loop, Jacquard allowed for exible, automated weaving. - Each card controlled a speci c weaving action, advancing the pattern with each click. - This invention revolutionized the textile industry and made Jacquard wealthy. - His use of punched cards for data storage was later adapted for early computer data input. Module Code & Module Title Slide Title 83 fi fl 1822 – Charles Babbage (1791-1871) and Ada Augusta, The Countess of Lovelace: - Charles Babbage, known as the Father of the modern computer, designed the Automatic Difference Engine to create mathematical tables for navigation. - However, due to engineering limitations of his time, it was never fully constructed. - Despite this setback, Babbage continued with a more ambitious project, laying the groundwork for modern computing concepts. Module Code & Module Title Slide Title 84 1822 – Charles Babbage (1791-1871) and Ada Augusta, The Countess of Lovelace: - Charles Babbage, while a professor at Cambridge, designed the Analytic Engine, an advanced machine with punched card input, memory (the store), arithmetic unit (the mill), automatic printout, sequential control, and 20-digit accuracy. - His design was a blueprint for a modern computer, 100 years ahead of its time, but it was never built due to technological limitations. - From 1842 to 1843, Ada Lovelace translated Luigi Menabrea's work on the Analytic Engine and added notes detailing a method for calculating Bernoulli numbers. - This is recognized as the rst computer program, and she is celebrated as the rst programmer, despite having an ill-received programming language named after her. Module Code & Module Title Slide Title 85 fi fi 1847 George Boole: - George Boole was an English mathematician and logician who is best known for creating Boolean logic in the mid-1800s. - His work established a formal system for representing logical statements and their relationships using binary values (true/false or 1/0). - This foundational concept became essential in computer science, particularly in the design of digital circuits and programming languages. - Boolean logic allows for the manipulation of binary variables and is used in search algorithms, database queries, and decision-making processes in computers. - Boole’s contributions signi cantly in uenced the development of modern computing and laid the groundwork for digital electronics. Module Code & Module Title Slide Title 86 fi fl  History of Modern Computers 1937: Mark I (Aiken, Harvard University, IBM): - In 1937, the Mark I, also known as the Harvard Mark I, was built by Howard Aiken at Harvard University with help from IBM. - It was one of the earliest computers, using electromechanical relays instead of modern electronic components. - This made it one of the rst computers to automate calculations, playing a big role in the early development of computing technology. - The Mark I was massive and could perform simple calculations, helping to pave the way for modern computers. Module Code & Module Title Slide Title 87 fi Atanasoff-Berry Computer (ABC) - 1939: First Fully Electronic Digital Computer Inventors: John Atanasoff & Clifford Berry Technology Used: Vacuum tubes for calculations Vacuum tubes are electronic components that were widely used in early computers before transistors were invented. They function as electronic switches that control the ow of electricity in circuits. In the case of the ABC, these vacuum tubes were used to carry out arithmetic operations and logical functions such as addition and subtraction. Key Features: ◦ Binary system for calculations ◦ Capacitor-based memory for storage ◦ Designed to solve linear algebraic equations Impact: Laid the foundation for modern digital computers. Module Code & Module Title Slide Title 88 fl ENIAC (1943-46): First General-Purpose Digital Computer Inventors: John Presper Eckert & John W. Mauchly Developed at: University of Pennsylvania Technology Used: ◦ Vacuum tubes for electronic switching and calculations ◦ Used for complex arithmetic and data processing tasks Key Features: ◦ Can be reprogrammed to solve different problems ◦ Built to calculate artillery ring tables for the U.S. Army Impact: ◦ Major step towards modern computing, showcasing versatility in computing tasks. Module Code & Module Title Slide Title 89 fi  1945 Von Neumann Architecture: The Von Neumann architecture, proposed by John von Neumann in 1945, is a computer design model that uses a single storage structure for both instructions (program code) and data. It forms the basis of most modern computers. Key Components: 1. Central Processing Unit (CPU): ◦ Arithmetic Logic Unit (ALU): Performs arithmetic and logic operations. ◦ Control Unit (CU): Directs the operation of the computer by interpreting instructions from memory. 2. Memory (RAM): Stores both data and instructions in the same location. 3. Input/Output Devices (I/O): Allow the computer to communicate with the outside world. 4. Bus System: A communication pathway that transfers data and instructions between components. Stored Program Concept The stored program concept is a principle where instructions for the computer are stored in memory alongside data. This allows the computer to: Fetch instructions from memory. Decode and execute them in sequence. This concept enables exibility, as the same hardware can run different programs without being physically recon gured. Module Code & Module Title Slide Title 90 fi fl  Von Neumann Architecture Module Code & Module Title Slide Title 91 Creation of the Transistor (1947): Inventors: John Bardeen, William Shockley, and Walter Brattain Developed at: Bell Labs Signi cance: Replaced vacuum tubes as a smaller, more ef cient, and reliable component for amplifying and switching electrical signals. Marked the beginning of the miniaturization of electronic devices. Key Features: Made from semiconductor materials like silicon or germanium. Consumed less power and generated less heat than vacuum tubes. Enabled the development of modern computers, radios, and telecommunications. Impact: Revolutionized electronics, leading to the development of integrated circuits and microchips. Module Code & Module Title Slide Title 92 fi fi EDVAC and IAS (1951-1952): EDVAC (Electronic Discrete Variable Automatic Computer) Developed by: John von Neumann and team. Key Features: ◦ First computer to use the stored-program concept, allowing instructions to be stored in memory. ◦ Designed to perform both arithmetic and logical operations. ◦ Used binary number system for ef cient data processing. Signi cance: ◦ In uenced the design of most modern computers. IAS (Institute for Advanced Study Computer) Developed at: Princeton University (Institute for Advanced Study). Key Features: ◦ Based on von Neumann's architecture (central processing unit, memory, and input/ output). ◦ Pioneered the use of modular systems for instructions and data storage. Signi cance: ◦ Foundation for subsequent computing systems and inspired the design of commercial computers like IBM's. Module Code & Module Title Slide Title 93 fl fi fi fi Module Code & Module Title Slide Title 94  System Software History 1. Era Without Operating Systems Key Idea: ◦ Early computers were purely hardware-driven, with no operating systems to manage tasks. ◦ Programs were entered manually, either through switches for individual bits or by connecting wires to panels to create speci c circuits. Impact: ◦ This process was labor-intensive and error-prone. ◦ Only one user could operate the machine at a time, emphasizing its single-user nature. Module Code & Module Title Slide Title 95 fi  2. The First Operating System (1953-54) Key Idea: ◦ General Motors Research Laboratories developed the rst operating system for the IBM 701 computer. ◦ This system introduced basic functionalities to manage input/output and simplify programming processes. Impact: ◦ Marked the beginning of structured software layers that separated users from direct hardware control. ◦ Reduced human errors and increased programming ef ciency. Module Code & Module Title Slide Title 96 fi fi  3. Early Operating Systems Here are details of the other foundational systems that followed: FORTRAN (FORmula TRANslation) Monitor System (FMS) Key Idea: ◦ Created to streamline the execution of FORTRAN programs. ◦ Enabled batch processing, which allowed multiple tasks to be executed sequentially without manual intervention. Impact: ◦ Reduced programming complexity by automating input/output processes. IBSYS Key Idea: ◦ Developed for IBM systems, IBSYS provided ef cient batch processing capabilities. ◦ It acted as a precursor to more advanced operating systems by managing task scheduling. Impact: ◦ Improved resource utilization and user experience on IBM computers. Module Code & Module Title Slide Title 97 fi  Share Operating System (SOS) Key Idea: ◦ A collaborative system focusing on resource sharing. ◦ Aimed at creating a standardized framework for multi-user environments. Impact: ◦ Pioneered the concept of sharing computational resources, paving the way for future multi-user systems. Module Code & Module Title Slide Title 98  Operating Systems Development 1. Master Control Program (MCP) - 1963 Key Idea: ◦ Developed by Burroughs Corporation for their B5000 series computers. ◦ MCP introduced advanced OS features like virtual memory, multiprocessing, and job scheduling. Impact: ◦ Considered the rst operating system to incorporate many features of modern operating systems. ◦ Set a benchmark for future OS development, particularly for handling multiple programs ef ciently. 2. OS/360 by IBM - 1964 Key Idea: ◦ Designed for IBM's System/360 family of computers. ◦ Focused on batch processing, enabling the sequential execution of jobs with minimal human intervention. ◦ Introduced the concept of standardization across hardware models, allowing the same OS to work on different systems. Impact: ◦ Revolutionized business computing by allowing compatibility across IBM hardware. ◦ Simpli ed programming processes and expanded the market for commercial computing. Module Code & Module Title Slide Title 99 fi fi fi