Computers can be categorized on the basis of: size and data handling capabilities.
Further, on the basis of data handling capabilities, computers can be divided into three types:
- Analogue Computer
- Digital Computer
- Hybrid Computer
- Analogue computer: They are designed so that they can process the analogue data. The data that can change continuously and do not have discrete values such as temperature, current, speed and pressure is known as Analogue data.
The continuous changes that physical quantity goes through are measured by analogue computers. The output rendered by them is generally in the form of a reading on a dial or scale.
Analogue computers don’t wait for the data to get converted into codes and numbers and rather accept the data from the measuring device directly.
Mercury meter and speedometer are the examples of analogue computer.
- Digital Computers: They are designed to perform logical operations and calculations at a high speed. A digital computer accepts raw data as numbers or digits and then, to produce output, it processes it with the programs stored in its memory. The modern computers like desktops and laptops fall under the category of digital computers.
- Hybrid Computer: It contains the features of both Digital and Analogue computers. It has accuracy and memory like digital computers and is fast like Analogue computers. It can process both discrete and continuous data and hence it is widely used in specialised applications where both digital and analogue data is processed, example being a petrol pump where a processor is used to convert the measurement of fuel flow into price and quantity.
On the basis of size, computers can be classified into five types:
- Supercomputers: They are the fastest in speed and the biggest in size and specialise in processing a huge amount of data. A supercomputer contains thousands of interconnected processors that help it process trillions of instructions in just a second.
Roger Cray developed the first Supercomputer in 1976. Supercomputers are specifically used in engineering and scientific applications such as nuclear energy research, scientific simulations, and weather forecasting.
- Mainframe computer: They have the capacity of supporting hundreds or thousands of users simultaneously and they can also support multiple programs at the same time. This means that different processes can be executed simultaneously by a Mainframe Computer. Hence, organisations that need to process and manage high volume of data find mainframe computers ideal for them. Telecom and banking sectors are examples of such organisations.
- Miniframe computer: It is a multiprocessing computer of midsize. It has the capacity of entertaining 4 to 200 users at one given time and consists of 2 or more processors. Miniframe computers are mostly used in departments and institutes for the tasks like inventory management, billing and accounting.
- Workstation: It is a single user computer designed for scientific or technical applications. It flaunts high speed graphic adapters, faster microprocessor and a large amount of RAM. It can perform specific jobs with great expertise. There are different types of workstation computers like engineering design workstation, graphic workstation and music workstation.
- Microcomputer: It is also known as Personal Computer. This general purpose computer is mainly designed for individual use. It consists of a microprocessor, which works as the Central Processing Unit, storage area, memory, and input and output unit. The most famous examples of Microcomputers are Desktop computers and Laptops.