Types of computers

Types of computers

Types of Computer

1.      On the basis of work performance, computer can be classified into three classes.

a.   Analog Computer

b.   Digital Computer

c.   Hybrid Computer

Analog Computer:

Analog Computers are very similar to measuring instruments such as voltmeter, thermometer, a slide rule or a plan meter. The quantities are measured before being fed to their inputs .The analog computer acts on the input, performs a number of mathematical operations and outputs the results in the form of a smooth graph from where the value can be read.

For example, the speed of a car (indicated by the speedometer) is measured by an analogous physical quantity i.e. a rate of rotation of the main drive shift since speed is the derivate of the distance traveled with respect to time the analogous measuring process consists of differentiation in this case. In addition to power supply, the main components of an analog computer are: operational amplifier and passive networks of resistors, capacitors and inductors.

Digital Computers:

 In Digital Computers, quantities are counted rather than measured. A numerical counting of the discrete data performs the computation essentially. For this purpose, all mathematical operations are broken down into "counting" or adding operations. Subtraction, division, multiplication and even powers and roots, integration and differentiation is, in effect, controlled arithmetic. Since a digital computer can store and handle vast masses of data, it is ideally suited for complex numerical and statistical problems in science, business and industry. Most computers in use today are digital computers. In fact, the word" computer" becomes synonymous with digital computer.

Hybrid Computers:

Hybrid Computer can do the tasks of digital as well as analog computer. The good qualities of an analog and digital machined are sometimes combined to create a Hybrid computer or hybrid computing system. Hybrid computers can transfer data from analog to digital and vice versa.

2.      On the basis of size the computers are classified as:

1. Micro Computer

.2. Mini Computer

3. Mainframe Computer

4. Super Computer

Micro Computers:

Micro computer is also known as personal computer or Home computer. they are made by using microprocessors, they are widely used at homes and offices. many brands, models, and sizes are available in microcomputers, they are used in many fields of business, education, desktop & graphics designing , data processing etc.

in other words, a small computer driven by a single integrated circuit and designed for use by one person is called micro computer it is also called PC.

i. Desktop computer

ii. Palmtop computer/Digital diary/ Notebook

Mini Computers:

Mini Computers are supposed to be more powerful than micros. They typically serve multiple users. They are usually more powerful and more expensive than micros.

Mainframe Computers:

Mainframe Computers are systems that offer faster processing speeds and greater storage capacity than a typical mini. The earlier computers were called mainframes due to their large size. Today mainframes are powerful and have large capacities. They can also process large amounts of data very quickly and have a high capacity of main store. more than 100 people can work at a time.

Super Computers:

Super Computers allow for faster processing since they use multiple processors and are capable of performing tasks in parallel. They typically follow a "Non Von Neumann' design multiple arithmetic logic unit's perform specialized operations.

3.      Classification base on the Brand:

There are many brands computers. Hundreds of companies are involved in computer manufacturing and they give their own brand name. But it is true that all commuters can be classified under three categories from the technological point of view.

v  IBM-personal computer

v  IBM-compatible computer

v  Apple/Macintosh computer

IBM-personal computer:

IBM (International Business machines) Corporation was established in the USA IBM started to manufacture mainframe computers in 1945. The computers manufactured by this company are called IBM Computers.

IBM-compatible computer:

IBM-Pc: The Micro Computers of IBM Company is called BM_PC (IBM personal computer). IBM Computers are reliable, strong and they possess high speed processing

IBM Compatible: The computers manufactured based on IBM principles are called IBM Compatible computers IBM Compatible Computers can perform all the tasks that an IBM computer does. IBM is the richest company in software. The software that can run in IBM computers can be equally operated in IBM Compatible Computers.

Apple/Macintosh computer:

Apple/Macintosh: In 1970 Apple company was established in USA .It has the determination to develop different types of computers, more than that of IBM in architecture and system configuration as well. The software used in Apple Macintosh is not compatible to IBM. New brand of Apple computer is Macintosh. Macintosh is easy to handle. Small mouse type of device is connected to the computer which is essential to operate the computer. This is called Mouse.

4.      Classification base on the model:

Basically, IBM computers are classified into three models.

C XT (extra Technology) Computer

C AT (Advance Technology) Computer

C PS/2(Personal System-2) Computer

XT (extra Technology) Computer:

XT Computers were based with the processor named 8086.Later, some changes were made in the main processor of the computer (CPU) and new model of processor was developed 8088.

AT (Advance Technology) Computer:

AT Computers are faster then XT computers, they have higher capacity of RAM and can do more tasks that XT. In AT machines, microprocessors used are8026SX, 80286DX, 80386SX, 80386DX.Those are the main processor (CPU).

PS/2(Personal System-2) Computer:

Ps/2 Model Computers are much faster than IBM or IBM compatible computers because its Architectural design is advanced. IBM developed this model in1990.