Chapter - 1 (1).pptx

Chapter - 1 Introduction to Computer and its Components  Introduction to Computer? The literal meaning of computer is a device that can calculate. The term “computer” is derived from a Latin term “compute,” which means ‘to calculate.’ Charles Babbage was the founder of the comp...

Chapter - 1 Introduction to Computer and its Components  Introduction to Computer? The literal meaning of computer is a device that can calculate. The term “computer” is derived from a Latin term “compute,” which means ‘to calculate.’ Charles Babbage was the founder of the computer. However, modern computers can do a lot more than calculate. Computer is an electronic device that receives input, stores or processes the input as per user instructions and provides output in desired format.  school, banks, shops, railway stations, hospital or your own home, computers are present everywhere, making our work easier and faster for us. As they are such integral parts of our lives, we must know what they are and how they function.  Computer input is called data and the output obtained after processing it, based on user’s instructions is called information.  Components of Computer A computer device is made up of various elements. There are five basic components of the computer which help in making processing of data easier and convenient which includes: 1. Input Unit 2. Output Unit 3. Memory Unit 4. Control Unit 5. Arithmetical and Logical Unit 1. Input Unit This unit contains devices with the help of which we enter data into the computer. This unit creates a link between the user and the computer. The input devices translate the information into a form understandable by the computer. 2. CPU (Central Processing Unit) CPU is considered as the brain of the computer. CPU performs all types of data processing operations. It stores data, intermediate results, and instructions (program). It controls the operation of all parts of the computer. CPU itself has the following three components − 1. ALU (Arithmetic Logic Unit) 2. Memory Unit 3. Control Unit 1. ALU (Arithmetic & Logic Unit) As the name suggests, all the mathematical calculations or arithmetic operations are performed in the Arithmetic and Logical Unit of the CPU. It can also perform actions like a comparison of data and decision-making actions. The ALU comprises circuits using which addition, subtraction, multiplication, division and other numerical based calculations can be performed. 2. Memory Unit Computer memory is any physical device capable of storing information temporarily like RAM (random access memory), or permanently, like ROM (read-only memory). Memory devices utilize integrated circuits and are used by operating systems, software, and hardware. 3. Output Unit The output unit consists of devices with the help of which we get the information from the computer. This unit is a link between the computer and the users. Output devices translate the computer's output into a form understandable by the users.  Advantages of Computer 1. Multitasking – Multitasking is one among the main advantage of computer. Person can do multiple task, multiple operation at a same time, calculate numerical problems within few seconds. 2. Speed – One of the most advantages of computer is its incredible speed, which helps human to finish their task in few seconds. 3. Accuracy – One among the basis advantage of computer is which will perform not only calculations but also with accuracy. 4. Data Security – Protecting digital data is understood as data security. 5. Task completer – Completes tasks that might be impossible for humans to complete. 6. Communication – Computer helps the user in better understanding and communication with the other devices. 7. Productivity – The level of productivity gets automatically doubled as the computer can done the work at very fast. 8. Reduces work load – Information are often accessed by more then one person with the necessity for work to be duplicated. 9. Reliability – Computers can perform same sort of work repeatedly without throwing up errors thanks to tiredness or boredom, which are quite common among humans. 10. Storage – The pc has an in-built memory where it can store an outsized amount of knowledge. You can also store data in auxiliary storage devices.  Disadvantages of computer 1. Virus and hacking attacks – Virus may be a worm and hacking is just an unauthorized access over computer. Virus can go to other system from email attachment, viewing an infected website advertisement, through removable device like USB etc. 2. Online Cyber Crimes – Online cyber-crime means computer and network may have utilized in order to commit crime. fraud are the points which comes under online cyber-crimes. 3. No I.Q A computer is a machine that has no intelligence to perform any task. Each instruction has to be given to computer. A computer cannot take any decision on its own. 4. Dependency It functions as per a user’s instruction, so it is fully dependent on human being 5. High cost Computers are expensive. Even the foremost affordable computers are still very expensive. 6. Environment The operating environment of computer should be dust free and suitable. 7. No Feeling Computers have no feelings or emotions. It cannot make judgment based on feeling, taste, experience, and knowledge unlike a human being. 8. Health Problems: – Prolonged use of computers can lead to various health Problems. Too much sitting near the screen results in eye strain and drying up of the eyes. Also, Long time sitting leads to neck and back problems.  Generations of Computer 1. First Generation The period 1940 to 1956, roughly considered as the First Generation of Computer. The first generation computers were developed by using vacuum tube or thermionic valve machine. The input of this system was based on punched cards and paper tape; however, the output was displayed on printouts. The first generation computers worked on binary-coded concept (i.e., language of 0,1). Examples: ENIAC, EDVAC, etc.  The First generation computer was very large and could also cover entire room. Computers of this generation generated too much heat and required a large cooling system. Storage capacity in computers was very law in this generation. 2. The Second Generation The period 1956 to 1963 is roughly considered as the period of Second Generation of Computers. The second generation computers were developed by using transistor technology. In comparison to the first generation, the size of second generation was smaller. In comparison to computers of the first generation, the computing time taken by the computers of the second generation was lesser. Examples are IBM 1401, IBM 7094 AND IBM 7090, UNIVAC 1107, and so on.  A cooling system was still needed in this generation. Second generation computers required maintenance at regular intervals. The cost of the computer was still high, however less then the first generation computer. 3. Third Generation The period 1963 to 1971 is roughly considered as the period of Third Generation of computers. The third generation computers were developed by using the Integrated Circuit (IC) technology.  In comparison to the computers of the second generation, the size of the computers of the third generation was smaller. The third generation computer consumed less power and also generated less heat. The maintenance cost of the computers in the third generation was also low. The computer system of the computers of the third generation was easier for commercial use.  Third generation computer also required cooling system. Production and maintenance of Integrated circuit were difficult at that time. The price of the third generation computer was still high for personal use. 4. Fourth Generation The period 1972 to 2010 is roughly considered as the fourth generation of computers. The fourth generation computers were developed by using microprocessor technology.  By coming to fourth generation, computer became very small in size, it became portable. The machine of fourth generation started generating very low amount of heat. It is much faster and accuracy became more reliable. A cooling fan was included in computers instead of an air conditioning system. 5. Fifth Generation The period 2010 to till date and beyond, roughly considered as the period of fifth generation of computers. By the time, the computer generation was being categorized on the basis of hardware only, but the fifth generation technology also included software. The computers of the fifth generation had high capability and large memory capacity. Working with computers of this generation was fast and multiple tasks could be performed simultaneously. Some of the popular advanced technologies of the fifth generation include Artificial intelligence, Quantum computation, Nanotechnology, Parallel processing, etc. Generations of Generations Evolving computers timeline hardware First generation 1940 to 1956 Vacuum tube based Second generation 1956 to 1963 Transistor based Integrated circuit Third generation 1963 to 1971 based Microprocessor based(VLSI- Very Fourth generation 1972 to 2010 Large Scale Integration) Artificial intelligence 2010 to till date and based Fifth generation beyond ( ULSI microprocessor based.)  Categories of Computer  The four basic types or Categories of computers: 1. Supercomputer. 2. Mainframe Computer. 3. Minicomputer. 4. Microcomputer. 1. Super Computer The highly calculation-intensive tasks can be effectively performed by means of supercomputers. The most powerful computers in terms of performance and data processing are the Supercomputers. These are specialized and task-specific computers used by large organizations. These computers are used for research and exploration purposes like NASA uses supercomputers for launching space shuttles, controlling them and for space exploration purpose.  Supercomputers are used for areas related to: 1. Science 2. Engineering 3. Education 4. Defense 5. Aerospace 2. Mainframe Computer Although Mainframes are not as powerful as supercomputers, certainly they are quite expensive, and many large firms & government organizations use Mainframes to run their business operations. The Mainframe computers can be accommodated in large air- conditioned rooms because of its size. Super-computers are the fastest computers with large data storage capacity, Mainframes can also process & store a large amount of data.  Mainframe computers are primarily used in : 1. Institutions 2. Research 3. Academics 4. Health care 5. Libraries 6. Large businesses 7. Financial institutions 8. Stock brokerage firms 9. Insurance agencies 3. Minicomputers Minicomputers are used by small businesses & firms. Minicomputers are also called as “Midrange Computers”. These are small machines and can be accommodated on a disk with not as processing and data storage capabilities as super-computers & Mainframes. These computers are not designed for a single user. Individual departments of a large company or organizations use Mini-computers for specific purposes. 4. Micro Computer Desktop computers, laptops, personal digital assistant (PDA), tablets & smart phones are all types of microcomputers. The micro-computers are widely used & the fastest growing computers. These computers are the cheapest among the other three types of computers. The Micro-computers are specially designed for general usages like entertainment, education and work purposes. Well, known manufacturers of Micro-computer are Dell, Apple, Samsung, Sony & Toshiba.  Applications of Computer Business Banking Insurance Education Marketing Communication 1. Business A computer has high speed of calculation, accuracy, reliability, or versatility which has made it an integrated part in all business organizations. Computer is used in business organizations for − 1. Payroll calculations 2. Budgeting 3. Sales analysis 4. Financial forecasting 2. Banking Today, banking is almost totally dependent on computers. Banks provide the following facilities − Online accounting facility, which includes checking current balance, making deposits and, checking interest charges, shares and etc. ATM machines which are completely automated are making it even easier for customers to deal with banks. 3. Insurance  Insurance companies are keeping all records up-to- date with the help of computers.  Insurance companies, finance houses, and stock broking firms are widely using computers for their concerns.  Insurance companies are maintaining a database of all clients with information showing − Procedure to continue with policies Starting date of the policies Next due installment of a policy Interests due 4. Education The computer helps in providing a lot of facilities in the education system. The computer provides a tool in the education system known as CBE (Computer Based Education). CBE involves control, delivery, and evaluation of learning. Computer education is rapidly increasing the graph of number of computer students. 5. Marketing In marketing, uses of the computer are following − Advertising − With computers, advertising professionals create art and graphics, write and revise copy, and print and ads with the goal of selling more products. Home Shopping − Home shopping has been made possible through the use of computerized catalogues that provide access to product information and permit direct entry of orders to be filled by the customers. 6. Communication Communication is a way to convey a message, an idea, a picture, or speech that is received and understood clearly and correctly by the person for whom it is meant. Some main areas in this category are − E-mail Chatting Usenet FTP Telnet  Basics of Computers – Software Concepts A set of instructions that achieve a single outcome are called program or procedure. Many programs functioning together to do a task make a software. There are three categories of software − 1. System Software 2. Application Software 3. Utility Software Let us discuss them in detail. 1. System Software Software required to run the hardware parts of the computer and other application software are called system software. System software acts as interface between hardware and user applications some example of system software is − 1. Operating System 2. Device Drivers 2. Application Software A software that performs a single task and nothing else is called application software. Application software are very specialized in their function and approach to solving a problem. A hospital management software will manage hospital activities and nothing else. Here are some commonly used application software − – Word processing – Spreadsheet – Presentation – Database management 3. Utility Software Application software that assist system software in doing their work is called utility software. Thus utility software is actually a cross between system software and application software. Examples of utility software include − Antivirus software Disk management tools File management tools Compression tools Backup tools  Processor A processor is an integrated electronic circuit that performs the calculations that run a computer. A processor performs arithmetical, logical, input/output (I/O) and other basic instructions that are passed from an operating system (OS). Most other processes are dependent on the operations of a processor. The terms processor, central processing unit (CPU) and microprocessor are commonly linked as synonyms. Most people use the word “processor” interchangeably with the term “CPU” nowadays. Processors lie at the heart of all modern computers, not only personal Computers.  CPU Clock Speed: The clock speed of a CPU or a processor refers to the number of instructions it can process in a second. It is measured in gigahertz. For example, a CPU with a clock speed of 4.0 GHz means it can process 4 billion instructions in a second. Types of CPU: CPUs are mostly manufactured by Intel and AMD, each of which manufactures its own types of CPUs.  Some of the basic types of CPUs are described below: Single Core CPU : Single Core is the oldest type of computer CPU, which was used in the 1970s. It has only one core to process different operations. It can start only one operation at a time; the CPU switches back and forth between different sets of data streams when more than one program runs. So, it is not suitable for multitasking as the performance will be reduced if more than one application runs. The performance of these CPUs is mainly dependent on the clock speed. Dual Core CPU: Dual Core CPU contains two cores in a single Integrated Circuit (IC). Although each core has its own controller and cache, they are linked together to work as a single unit and thus can perform faster than the single-core processors and can handle multitasking more efficiently than Single Core processors. Quad Core CPU: This type of CPU comes with two dual-core processors in one integrated circuit (IC) or chip. So, a quad-core processor is a chip that contains four independent units called cores. These cores read and execute instructions from the CPU. The cores can run multiple instructions simultaneously.  Data Representation The binary digits or bits are used to show the digital data, which is represented by 0 and 1. The binary digits can be called the smallest unit of information in a computer. The main use of binary digit is that it can store the information or data in the form of 0s and 1s. It contains a value that can be on/off or true/false. On or true will be represented by the 1, and off or false will be represented by the 0. The digital file is a simple file, which is used to collect data contained by the storage medium like the flash drive, CD, hard disk, or DVD. Types of Computer Memory  In the computer system, we need computer memory to store various types of data like text, images, video, audio, documents, etc. We can retrieve it when the data is required. For example, when we write and execute any computer program, it is initially stored in primary memory. Random Access Memory (RAM) It is also called read-write memory or the main memory or the primary memory. The programs and data that the CPU requires during the execution of a program are stored in this memory. It is a volatile memory as the data is lost when the power is turned off. RAM is further classified into two types- SRAM (Static Random Access Memory) and DRAM (Dynamic Random Access Memory). DRAM: Dynamic Random-Access Memory is a type of RAM that is used for the dynamic storage of data in RAM. Characteristics of DRAM It requires continuously refreshed to retain the data. It is slower than SRAM It holds a large amount of data It is the combination of capacitor and transistor It is less expensive as compared to SRAM  SRAM: SRAM (Static Random-Access Memory) is a type of RAM used to store static data in the memory. It means to store data in SRAM remains active as long as the computer system has a power supply. However, data is lost in SRAM when power failures have occurred. Characteristics of Static RAM It does not require to refresh. It is faster than DRAM It is expensive. High power consumption Longer life Large size Uses as a cache memory Read-Only Memory (ROM) Stores crucial information essential to operate the system, like the program essential to boot the computer. It is not volatile. Always retains its data. Used in embedded systems or where the programming needs no change. Used in calculators and peripheral devices. ROM is further classified into four types-PROM, EPROM , and EEPROM. Types of Read-Only Memory (ROM) 1. PROM (Programmable read-only memory) – It can be programmed by the user. Once programmed, the data and instructions in it cannot be changed. 2. EPROM (Erasable Programmable read-only memory) – It can be reprogrammed. To erase data from it, expose it to ultraviolet light. To reprogram it, erase all the previous data. 3. EEPROM (Electrically erasable programmable read-only memory) – The data can be erased by applying an electric field, with no need for ultraviolet light. We can erase only portions of the chip.  RAM V/S. ROM RAM ROM It is a Random-Access It is a Read Only Memory. Memory. Read and write operations Only Read operation can can be performed. be performed. Data can be lost when the Data cannot be lost when power supply is turned off. the power supply is turned off. It is a faster and expensive It is a slower and less memory. expensive memory. Storage data requires to Storage data does not be refreshed in RAM. need to be refreshed in ROM.  Secondary Storage Device HDD (Hard Disk Drive) HDD is an electro-mechanical storage device, which is an abbreviation of Hard Disk Drive. It uses magnetic storage for storing and retrieving the digital data. It is a non-volatile storage device. Hard Disk Drive is installed internally in our computer systems, which is connected directly to the disk controllers of the motherboard. SSD (Solid State Drive) SSD is a non-volatile storage device, which stands for Solid State Drive. SSD stores the data on flash memory chips and maintains the data in a permanent state, even when the power is off. Sometimes, this storage device is also called as a solid-state disk or solid-state device. These storage devices store the data in the semiconductor cells. Unlike the HDDs (Hard Disk Drives), SSDs do not have any moving parts. That's why they are called solid-state drives. CD (Compact Disk) A compact disc (CD) is a circular disc introduced by James Russell. It is 4.75 inch in diameter, which is a flat, round, portable storage medium used to record, store and playback audio, video, and other data. Floppy Disk A floppy disk is a type of storage media that reads data storage information, also known as a floppy diskette, floppy, or floppy disk that is used to store electronic data, like a computer file. It was extremely expensive as it was one of the first types of hardware storage created in 1967 by IBM, which could read/write a portable device. Magnetic Tap In magnetic tape only one side of the ribbon is used for storing data. It is sequential memory which contains thin plastic ribbon to store data and coated by magnetic oxide. Data read/write speed is slower because of sequential access. It is highly reliable which requires magnetic tape drive writing and reading data.  Expansion Slots and Adaptor Cards Alternatively known as a bus slot or expansion port, an expansion slot is a connection or port inside a computer on the motherboard. It provides an installation point for a hardware expansion card to be connected. For example, if you wanted to install a new video card in the computer, you'd purchase a video expansion card and install that card into the compatible expansion slot. It is circuit board that provide connection to peripherals. That peripheral device controlled by processor. Ex. Modems, disk driver, Video card, Sound, Network Card  Ports and Connectors A port is point at which a peripheral attaches to communicate with system unit. The peripheral can send and receive data from computer. Port have different types of connectors. A connector joins a cable to peripherals. 1. Serial Port Used for external modems and older computer mouse Two versions: 9 pin, 25 pin model Data travels at 115 kilobits per second 2. Parallel Port Used for scanners and printers Also called printer port 25 pin model 3. PS/2 Port Used for old computer keyboard and mouse Also called mouse port Most of the old computers provide two PS/2 port, each for the mouse and keyboard 4. Universal Serial Bus (or USB) Port It can connect all kinds of external USB devices such as external hard disk, printer, scanner, mouse, keyboard, etc. It was introduced in 1997. Most of the computers provide two USB ports as minimum. Data travels at 12 megabits per seconds. USB compliant devices can get power from a USB port. 5. VGA Port (Video Graphics Array) Connects monitor to a computer's video card. It has 15 holes. Similar to the serial port connector. 6. RJ-45 (Registered Jack) It is an Ethernet style network port found on the computer and other devices such as routers, switches, etc. This port allows your computer to interact or communicate with other computers and networking devices where Ethernet networking is required. 7. Ethernet Port: Ethernet Port helps to connect to a network and high-speed Internet(provided by LAN or other sources). It connects the network cable to a computer and resides in a Ethernet card. It provides a data travel speed of 10 Mb to 1000 Mb per second. What are Connectors? A connector is any connector used within computers or to connect computers to network, printers or other devices.  BUSES The computer buses are used to connect the various hardware components that are parts of computer system. Various devices attached to the system unit to communicate with each other. Buses transfer bits from input device to memory , from memory to processor, from processor to memory, and from memory to output device  SMPS Switch mode power supplies (SMPSs) are used in a range of applications as an efficient and effective source of power. This is in major part to their efficiency. For anybody still working on a desktop, look for the fan output in the central processing units (CPU). That’s where the SMPS is. SMPS offers advantages in terms of size, weight, cost, efficiency and overall performance. These have become an accepted part of electronics gadgets. Basically, it is a device in which energy conversion and regulation is provided by power semiconductors that are continuously switching “on” and “off” with high frequency. It convers power from AC( Alternating current ) to DC (Direct Current). It provides stable voltage for all devices. What is PoS and ATM? ATM/POS means all Automated Teller Machines or Point-of-Sale machines operated or affiliated to Postbank