What is a Computer?
A computer is an electronic device that manipulates information, or "data." It has the ability to store, retrieve, and process data. You can use a computer to type documents, send email, and browse the internet. You can also use it to handle spreadsheets, accounting, database management, presentations, games, and many more.
How does a computer work with?
1. Computer hardware equals the collection of physical elements that comprise a computer system. Computer hardware refers to the physical parts or components of a computer such as monitor, keyboard, Computer data storage, hard drive disk, mouse, printers, CPU (graphic cards, sound cards, memory, motherboard and chips), etc all of which are physical objects that you can actually touch. In contrast, software is untouchable. Software exists as ideas, application, concepts, and symbols, but it has no substance. A combination of hardware and software forms a usable computing system. 2. Computer software, or just software, is any set of machine-readable instructions (most often in the form of a computer program) that directs a computer's processor to perform specific operations. The term is used to contrast with computer hardware, the physical objects (processor and related devices) that carry out the instructions. Hardware and software require each other; neither has any value without the other.
Firmware is software that has been permanently stored in hardware (specifically in non-volatile memory). It thus has qualities of both software and hardware.
Software is a general term. It can refer to all computer instructions in general or to any specific set of computer instructions. It is inclusive of both machine instructions (the binary code that the processor understands) and source code (more human-understandable instructions that must be rendered into machine code by compilers or interpreters before being executed).
On most computer platforms, software can be grouped into two broad
3. Human ware: Who operates computer with hardware and software.
Classification of Computers Based on Size:
Nowadays, computers are available in different sizes and with different capabilities. On the basis if storage capacity of speed of processing information computers are classified into: 1. Super computers
2. Mainframe computers
3. Mini computers
4. Micro computers
|The Columbia Supercomputer at NASA |
They are most powerful and expensive. They have extremely large storage capacities and processing speed is at least 10 times faster than other computers. They are big machines, Inside super computers, they are several smaller computers, each of which can work on different parts of a work simultaneously. It can calculate about 400 million numbers every second, and result is always exactly correct
They are medium or large machines , made of several units connected together . Mainframe computers are generally used in big organizations and government departments for large-scale date processing. Their processing capabilities vary from computers to computers ranging to million of bytes per second.
c) Mini Computer
• These are also a general purpose computer, smaller than mainframe computer. Medium sized computer, occupying approximately 10 sq ft of area. • They have slower operating speed, smaller backup storage, limited hardware and less memory than mainframes. • Minicomputers are well adapted for functions such as accounting, word processing, data base management, statistical packages for social sciences • More than 50 terminals and large storage capacity device than micro computers but smaller than mainframe computers. E.g. Prime 9755