Computer Fundamentals

Course Outline

• Course topics include computer science history, the origin of computing machines, computer hardware, modern I/O units, diverse digital applications, and the role of information processing in society.

Fundamentals of a Computer

• A computer processes data electronically to produce results.
• Received data becomes input; the processed result becomes output or information.
• Computers store data/information in memory for future access.
• Hardware and software are the two main parts of a computer, analogous to the body and spirit/soul of a human being.
• Hardware is the physical, tangible part; software is intangible code.
• Software resides and operates within the hardware to run the computer.
• Capable of processing numerical data as 0s and 1s, in binary digital format referred to as "bits." Binary digit is shortened to bits.
• A bit is the smallest unit of information a computer can process.
• Bits have one of two values: 0 or 1.
• Digital format forms the basis of machine language.
• Machine language differs from human-readable languages, but computers can solve repetitive computational tasks depending on speed and timeliness.
• A byte is a collection of 8 bits and can represent 256 different messages (256 = 28)
• Kilobyte, megabyte, gigabyte, and terabyte describe large data units used in measuring data storage
• Example: 100 GB hard drive; 8 bits = 1 Byte; 1024 Bytes = 1 Kilobyte (KB); 1,048,576 Bytes = 1 Megabyte (MB); 1,043,741,824 Bytes = 1 Gigabyte (GB); 1,099,511,627,776 Bytes = 1 Terabyte (TB)
• A computer system involves a complete suite of hardware and software resources as well as the users that operate the computer system.
• Different kinds of computer systems can handle certain specific additional functionalities.
• Ideally, a full-fledged computer system is made up of users, application software, and systems software.

What Computers Do

• Four basic operations: receive input, process information, produce output, and store information.
• Receive input: Accept information from the outside world.
• Process information: Perform arithmetic or logical operations on information.
• Produce output: Communicate information to the outside world.
• Store information: Store and retrieve information from memory and storage devices.

Components of a computer System

• Central Processing Unit (CPU): Arithmetic Logical Unit (ALU), Control Unit (CU), Memory Unit (MU); also interacts with input and output

Classifications of Computers

• Personal computers (PCs) are common, cheaper, versatile, small, portable, and single-user. Laptops are a type of PC.
• Workstations are more powerful than PCs and also single-user. They have higher specifications and quality.
• Minicomputers are multi-user computers, supporting many concurrent users for larger, complex computational jobs. They belong to large organizations and connect PCs and workstations in a network.
• Mainframe computers are larger, expensive, powerful multi-user systems supporting thousands of concurrent users. They are found often in large corporations.
• Supercomputers, performing hundreds of millions of instructions per second, solve grand challenge problems that are data- and computationally intensive.

Historical Generations of Computers

• Computer history dates back to 1833, when Charles Babbage invented the first runner of digital programmable computers.
• The Electronic Numerical Integrator and Computer (ENIAC), the first general-purpose electronic computer, was invented by John W. Mauchly and J. Presper Eckert.
• First Generation (1940-1956): Used vacuum tubes for logic circuitry.
• Magnetic drums stored data and transferred it. Machine language was developed for programming. ENIAC was developed during this period. Drawbacks included high cost.
• Second Generation (1957-1963): Transistors were used as switching devices, making computers smaller, faster, and more energy-efficient. Assembly languages were the typical programming format.
• Third Generation (1964-1971): Integrated circuits (IC) were used as switching devices, making computers smaller, faster, and more efficient. High-level programming languages were introduced.
• Fourth Generation (1972-1990): Microprocessors were the central processing units (CPU). Personal computers were manufactured, and Very Large Scale Integrated (VLSI) circuits technology was implemented.
• Fifth Generation (1990-Present): Based on superconductors, VLSI, miniaturized components, multi-core technologies, and artificial intelligence.

Modern Input/Output Units

• Input devices: keyboard, mouse etc.
• Output devices: printer, monitor, speaker etc.
• Secondary storage devices: hard disk, CD, DVD etc.
• Internal components: CPU, motherboard, RAM etc.

Input Devices

• An input device is any hardware component that allows users to enter data and instructions.
• Two types of input: data and instructions.
• Data is unprocessed text, numbers, images, audio, and video
• Instructions include programs, commands, and user responses.
• A keyboard allows computer users to enter words, numbers, punctuation, symbols, and special function commands.
• A pointing device controls the movement of the pointer; also called a a mouse.
• Other input devices: touchpad, pointing stick, joystick, wheel, touchscreen.
• Sound and voice input uses musical instrument digital interface (MIDI) and microphones.
• Video input converts analog video signals int digital signals.
• A scanner is a light-sensing device that reads printed text and graphics.

Data Projector

• Device that projects image from computer screen onto larger screen.

The Central Processing Unit (CPU)

• Interprets and carries out basic instructions that operate a computer. Is also called the processor.
• The CPU consists of a control unit and an arithmetic logic unit (ALU).
• Control unit directs and coordinates operations in the computer.
• Arithmetic logic unit (ALU) performs arithmetic, comparison, and logical operations
• Fetch, decode, execute, and store describes the four operations of the instructions comprising a machine cycle.
• The CPU transforms input into output. It interprets, exectutes instructions in program, performs arithmetic/logical data manipulations and communicates indirectly through memory.
• Modern microprocessors consist of electronic circuits housed with chips and motherboard
• The motherboard contains the computer's CPU.
• Typical CPUs are divided into functional units like the control unit, arithmetic logic unit (ALU), decode unit, bus unit, and prefetch unit.

Parallel Processing

• Uses multiple processors simultaneously to execute programs with special software designed to divide problems and merge results.

Computer Memory

• Is used to store data, instructions, and the processed results of processed data for computing. It consists of cache memory, primary/main memory, and secondary memory.
• Cache Memory is a high-speed memory that stores copies of data from frequently used main memory locations. If present, the processor immediately reads from or writes to cache for faster results.
• Cache helps speed computer processes by storing frequently used instructions and data. Is also called memory cache
• Primary memory, also known as main memory, stores current data, programs, and instructions. Examples are RAM, ROM, cache, PROM, and EPROM. Data can be read and written at a fast pace.
• Primary memory is broadly classified as Read-Only Memory (ROM) and Random Access Memory (RAM).
• Read-Only Memory (ROM) stores data that need not be altered and includes programs for booting the system with system algorithms. ROM information is etched on the ship when manufactured and consists of start up in structions and crticial information.
• Random Access Memory (RAM) loads processes to be executed by the CPU and stores program instrcutions and data temporarily. Each location is assigned to an address and is rated by both size and speed as a DIMMS.
• RAM is volatile (disappears when power is turned off)and are the most common type of primary storage
• There are two basic types of RAM chips, being static and dynamic. Newer RAM is magneto resistive (MRAM).