The Anatomy Of A Computer

Published Date: 02 Nov 2017

An automatic electronic apparatus for making calculations or controlling operations those are expressible in numerical or logical terms.

Anatomy of a Computer

A system is a set of components that work together to accomplish one or more common goals. A computer system can be viewed as a system of three major components.

Computer Hardware

Computer Software

Computer Liveware (Personnel)

Classification of computers

Computers can be classified into different categories based on the following criteria.

Types of data processed

Functions performed

Processing capabilities

Classification of computers according to the type of data processed

Analog Computers

In analog computers, data is represented as continuously varying and operates essentially by measuring rather counting. As the data is continuously variable, the results obtained are estimated and not exactly repeatable. Voltage, temperature and pressure are assured using devices like voltmeters, thermometers etc.

Digital Computers

In digital computers, data is represented as discrete units of electrical pulsars. The data is measured in quantities represented as either the ON or OFF state. Therefore, the results obtained from a digital computer are measured and precise. The modern day digital clock is a good example. Virtually all of today’s computers are based on digital principles.

Hybrid Computers

Hybrid computer accepts data in analog form and present output also in analog form. The data, however, is processed digitally. Therefore, hybrid computers required analog digital converters for input and digital to analog converters for output.

Classifying computers according to their functions pertained

Special Purpose Computer

Special purpose computers are also known as dedicated computers. They are designed to solve a single type of problem. The functions are uniquely adapted to control situations.

Many computers are special purpose computers designed as computerized traffic control systems and automatic aircraft landing systems. Examples of special designed computers that could need to operate in real time are those involved in process control, missile obtained data and light control.

General Purpose Computer

General Purpose computers are designed to be flexible and versatile. They can be used to solve a verity of problems by changing the program or instructions that govern their operations. The range of problems that can be solved by a General Purpose Computer stretches from the simplest accounting to the most complex simulation and forecasting.

Classification of Computers

Size

Modern computers vary in size from large computers that fill entire rooms to the CPU that is smaller in size than the nail of the little finger.

Computers can thus be classified as Supercomputers, Mainframe Computers, Minicomputers and Microcomputers according to their size.

While large systems have grater processor speed, greater storage capacity, are able to handle large number of powerful input and output devices, the smaller processors are generally cater to single uses. They may be special purpose devices performing a single task example controlling the ignition system in an automobile. Personal computers are ranging from the Desktop model to the laptop, to the Notebook.

Micro-Computers

The microcomputer is the smallest type of computer available. Inside the microcomputer, the arithmetic and control unit is combined on a single chip called a microprocessor.

Microcomputer contains two types of store or memory. Random Access Memory (RAM) where programs and data are held during processing temporarily. Data stored in the RAM is lost when the machine is switched off.

Read Only Memory (ROM) where permanent instructions of data are held. The wrong does not require a continuous supply of power to retain its contents.

Microcomputer site is used as home computers for the family or as personal computers by business executives or by small businesses where volumes of data processing and speed requirements are small.

Mainframes

The earliest computers were called mainframes due to their large size. The term is still used for the large computers today. The capacities of the earlier mainframes and the mainframes of today are numerous to different. Mainframes are very large computers with a very high capacity of main store. Because they can process large amounts of data are very quickly; big companies, banks, government departments as their main computer use them. They can be linked into a network with smaller departmental computers, Microcomputers or with each-other. They act as hosts of larger national and international communication networks, handling hundreds of users. Some examples of mainframes are IBM 4381, ICL 39 series and CDC cyber series.

Supercomputers

Complex and difficult applications like weather forecasting require a large amount of data to be manipulated within a very short time. Large supercomputers are with faster processing using multiple processors and superior technology. Examples of supercomputers are CARY XMP-24 and NEC-500.

Laptop computer

Portable power came of age towards the end of the 1980s. Our some laptop portables now have the same capacity as some of the larger microcomputers. In 1994 Intel’s powerful Pentium processor found its way into portables too. 64 or 128MB (megabytes) of main memory, together with the medium capacity hard disk and a coloured monitor were commonplace by 2000. In addition to this, the laptop portable can have sophisticated communications facilities. It is these portables and a revolution iced their way in which many people use their computers. If you have a computer available whenever you are, then you’re most likely to make use of it.

Palmtop

A computer that is small enough to fit in the palm of one’s hand. Palmtops or hand-held personal computers are lightweight, small, battery-powered, general-purpose programmable computers.

1.2.1 Computer Hardwear

The word hardwear refers to the tangible things that make up a computer such as display unit, system unit, keyboard, mouse, etc. System unit is the place where the "brain" of the computer exists.

A computer system is a combination of six electronic hardwear, softwear, data and information, procedures or intrusions people and communities.

Generally computer hardwear can be divided into five categories.

Input devices

Processors

Storage devices

Output devices

Communications

1.2.1.1 Input devices

Input devices are used to input data, processed and programs that include processing instructions to the computer. Common input devices are the keyboard and the mouse. There are other input devices such as pointing devices, scanning devices, writing cards, and optical cards, sensors, digital cameras, trackballs, joystick, touch screens, light pen, barcode readers, optical character reader, microphone, etc.

1.2.1.2 Processors

The processor in a personal computer (PC) is generally considered as the PC’s "brain". It process instructions and also manipulates data.

1.2.1.3 Storage or memory devices

The word storage implies the retaining (holding place) of information temporally or permanently. There are two types of storage devices namely: Primary storage devices and Secondary storage devices. There are two types of memory: RAM (Random Access Memory) and ROM (Read Only Memory)

Primary Storage or memory devices: this refers to computer’s internal memory, which is typically made of RAM (Random Access Memory).

Characteristic of RAM

Temporarily stored data

Can store and retrieve data much faster

Volatile (Changing, not stable)

Small memory capacity