Perfect Computer Notes

Q. Write a note on Classification of Computers    OR Explain Types of computer on the basis of Size, Shape and Resources. OR How digital computers are classified? Classification of Computers Computers are classified on the basis of size, speed and price as under: •    Microcomputer or Personal Computer •    Mini Computer •    Mainframe Computer •    Super Computer 1. Micro Computers Desktop Model computer Micro computer is also called personal computer. It was introduced in 1970. It contains  input devices, output device, storage device, memory and processor. It is used by one person at a time. Examples of personal computers are PC and Apple Macintosh. The major types of personal computers are desktop computer and portable computer. Desktop Computers These computers can easily fit on a table or desktop, hence the name. These computers come in two models or casings. In Desktop model, the system unit is placed on the desktop or table. Monitor is placed on the system unit

Following are the main basic units or components of the computer : 1. Input Unit 2. Output Unit 3. Central Processing Unit( CPU / Processor) 4. Memory Unit 5. Storage Unit Diagram Showing Main Components or Basic Units of a Computer Different Basic Units or fundamental components of a computer Brief Description of Basic components of Computer 1. Input Unit Input unit consists of input devices . Input devices are used to enter data and instructions into computer memory. Examples of input devices are Keyboard, mouse, joystick and microphone etc. 2. Output Unit Output unit consists of output devices . Output devices are used to show results produced by computer after data processing. Examples of output devices are Monitor, Printer, plotter and  speaker etc. 3. Central Processing Unit Central processing unit is also called CPU or Processor . It is the brain of the computer. It performs data processing. It controls overall operations and

Computers can be divided into the following 3 types on the basis of their working mechanism: 1) Analog Computers 2) Digital Computers 3) Hybrid Computers 1. Analog Computers Analog computer is used to measure continuous values. It measures a physical property like voltage, pressure, speed, time and temperature. An analog computer takes input in analog form and gives output in analog form. Its output is usually displayed on a meter or scale. Analog computer has low memory and fewer functions. Analog computer is mainly used in the field of engineering and medicine. Examples include: Examples of Analog Computers include:  1. Thermometer 2. Speedometer 3. Analog clock 2. Digital Computers A digital computer works with digital data. Digital computer uses binary number system. Binary number system consists of only two digits 0 and 1. A digital computer represents data in digital signals. A 0 represents OFF and a 1 represents ON. Digital computer performs arith