What is Computer
What is computer?
A computer is an electronic device, which accepts input, manipulate the inputs and generate a meaningful output, or a computer is an electronic machine that is fed with data or information, processes or works on the data, and give out information. The data or information fed into the computer is referred to as the input, and the result or information is the output. The data is handled in the computer by a combination of systems that either process it directly or serve as accompanying storage systems. A computer can store vast amounts of information, which could fill thousands of pages, and can find any of that information in fractions of a second. It can perform calculations that would take a person weeks or even years to do. But, unlike a person it cannot think for itself, it has to be told what to do. This is done by giving the computer a list of instructions called a program.
Type of computer
Digital Computer
Analogue Computer
Hybrid Computer
A computer is an electronic device, which accepts input, manipulate the inputs and generate a meaningful output, or a computer is an electronic machine that is fed with data or information, processes or works on the data, and give out information. The data or information fed into the computer is referred to as the input, and the result or information is the output. The data is handled in the computer by a combination of systems that either process it directly or serve as accompanying storage systems. A computer can store vast amounts of information, which could fill thousands of pages, and can find any of that information in fractions of a second. It can perform calculations that would take a person weeks or even years to do. But, unlike a person it cannot think for itself, it has to be told what to do. This is done by giving the computer a list of instructions called a program.
Type of computer
Digital Computer
Analogue Computer
Hybrid Computer
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Digital Computer
A digital computer is designed to solve mathematical problems or to count precisely. An example is a money – counting machine, a calculator etc. Analogue Computer An analogue computer is designed to, or measure quantities such as speed, pressure, temperature, voltage etc an e.g. is an automobile speedometer. Hybrid Computer A Hybrid computer is designed to perform the functions of both Analogue computer and Digital computer an example is a Personal Computer (PC). |
Classes of Computer
Computers can be generally classified by size and power as follows, though there is considerable overlap:
PERSONAL COMPUTER: Personal computer can support only one monitor, keyboard and other peripherals at a time. It is designed for independent use and has a low storage capacity and a low processing speed as compared to the other classes WORKSTATION: A powerful, single-user computer. A workstation is like a personal computer, but it has a more powerful microprocessor and, in general, a higher-quality monitor. MINICOMPUTER: Minicomputers are smaller in size as compared to mainframe computer. It has a large storage capacity and a high processing speed. It can also support more than one printer and monitor and other peripherals at a time. A multi-user computer capable of supporting up to hundreds of users simultaneously. MAINFRAME: Mainframe Computers are the largest computer. It also has a very large storage capacity and a high processing speed. It can support two or more monitors, keyboards and other peripherals at a time. It can also process numerous programs concurrently and can be used by many people at a time. . SUPERCOMPUTER: Super Computers are the most powerful computers. It has a very high processing speed and storage capacity. It is usually used by large organization for research purposes like oil exploration and weather forecasting. |
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PERSONAL COMPUTER
It can be defined as a small, relatively inexpensive computer designed for an individual user. Businesses use personal computers for word processing, accounting, desktop publishing, and for running spreadsheet and database management applications. At home, the most popular use for personal computers is for playing games and recently for surfing the Internet. Personal computers first appeared in the late 1970s. One of the first and most popular personal computers was the Apple II, introduced in 1977 by Apple Computer. During the late 1970s and early 1980s, new models and competing operating systems seemed to appear daily. Then, in 1981, IBM entered the fray with its first personal computer, known as the IBM PC. The IBM PC quickly became the personal computer of choice, and most other personal computer manufacturers fell by the wayside. P.C. is short for personal computer or IBM PC. However, in recent years, the term PC has become more and more difficult to pin down. In general, though, it applies to any personal computer based on an Intel microprocessor, or on an Intel-compatible microprocessor. For nearly every other component, including the operating system, there are several options, all of which fall under the rubric of PC PERSONAL COMPUTER TYPES Actual personal computers can be generally classified by size and chassis / case. The chassis or case is the metal frame that serves as the structural support for electronic components. Every computer system requires at least one chassis to house the circuit boards and wiring. The chassis also contains slots for expansion boards. If you want to insert more boards than there are slots, you will need an expansion chassis, which provides additional slots. There are two basic flavors of chassis designs–desktop models and tower models–but there are many variations on these two basic types. Then come the portable computers that are computers small enough to carry. Portable computers include notebook and subnotebook computers, hand-held computers, palmtops, and PDAs. TOWER MODEL The term refers to a computer in which the power supply, motherboard, and mass storage devices are stacked on top of each other in a cabinet. This is in contrast to desktop models, in which these components are housed in a more compact box. |
The main advantage of tower models is that there are fewer space constraints, which makes installation of additional storage devices easier.
DESKTOP MODEL A computer designed to fit comfortably on top of a desk, typically with the monitor sitting on top of the computer. Desktop model computers are broad and low, whereas tower model computers are narrow and tall. Because of their shape, desktop model computers are generally limited to three internal mass storage devices. Desktop models designed to be very small are sometimes referred to as slimline models. |
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PARTS OF PERSONAL COMPUTER
Main hardware components of a personal computer
Your PC (Personal Computer) is a system, consisting of many components. Some of those components, like Windows XP, and all your other programs, are software. The stuff you can actually see and touch, and would likely break if you threw it out a fifth-story window, is hardware.
Not everybody has exactly the same hardware. But those of you who have a desktop system, like the example shown above, probably have most of the components shown above. Those of you with notebook computers probably have most of the same components. Only in your case the components are all integrated into a single book-sized portable unit.
But there are three (3) main hardware components of a personal computer are as follows:
- Monitor
- System Unit
- Keyboard
Your PC (Personal Computer) is a system, consisting of many components. Some of those components, like Windows XP, and all your other programs, are software. The stuff you can actually see and touch, and would likely break if you threw it out a fifth-story window, is hardware.
Not everybody has exactly the same hardware. But those of you who have a desktop system, like the example shown above, probably have most of the components shown above. Those of you with notebook computers probably have most of the same components. Only in your case the components are all integrated into a single book-sized portable unit.
But there are three (3) main hardware components of a personal computer are as follows:
- Monitor
- System Unit
- Keyboard