In this part of the ‘Part 2’ article, I intend to focus on computer classification. It is of great importance to know which classification a particular computer system belongs to, as this will help to clearly differentiate between them when they are found.
Computer Classification:
In this section we give the classification of computers by the type of data they process, Purpose and Physical Size.
Classification by data process:
Digital computers:
Digital computers convert all input data into binary form; processes the data in binary form but the processed information is converted back to decimal form. The output of digital computers are usually discrete values. Digital computers are very precise; examples include desktop calculators, some personal computers, and adding machines. Most business applications use digital computers.
Analog computers:
Analog computers represent data continuously using physical quantities. Its accuracy depends on the measurement made and is therefore not as accurate as digital computers. These types of computers are used for scientific or engineering purposes. Examples include fuel pumps, speedometers, voltammeters, and all such instruments.
Hybrid Computer:
Hybrid computers combine the best features of analog and digital computers. Using digitizers, hybrid computers accept analog inputs and output digital values. They are used in highly scientific settings. The hybrid has the speed of analog and the precision of digital computers.
Classification by Purpose
Using this base, the two main classes are explained below:
Special Purpose Computers:
They are computers designed to perform specific tasks. They have built-in programs, which are stored in a part of main memory called read-only memory (ROM). The contents of this type of memory can be accessed and executed by the computer but cannot be modified by the user. Some examples are computers designed for use in digital watches.
General Purpose Computers:
These are computers that are not specifically designed or built for specific jobs. They solve various types of problems depending on the program or software loaded on them. Your main memory is usually Random Access Memory (RAM). Examples of this type of computers are found in the business, commercial and scientific environment.
Classification by physical size:
Microcomputer: The microcomputer is at the lower end of the computer spectrum in terms of speed and storage capacity. Your CPU is a microprocessor. The first microprocessors were built with 8-bit microprocessor chips. The most common application of personal computers (PCs) is in this category. The PC supports various input and output devices. Examples of microcomputers are IBM PC, PC-AT, etc.
Mini Computer – This is designed to support more than one user at a time. It has large storage capacity and operates at higher speed. The mini computer is used in a multi-user system where several users can work at the same time. This type of computer is generally used to process large volumes of data in an organization. They are also used as servers on local area networks (LANs).
Mainframes: These types of computers are generally 32-bit microprocessors. They run at very high speed, have a large storage capacity, and can handle the workload of many users. They are generally used in centralized databases. They are also used as control nodes in wide area networks (WANs). Some examples are DEC, ICL and IBM 3000 series.
Supercomputer: They are the fastest and most expensive machines. They have a high processing speed compared to other computers. They also have multiprocessing technique. One of the ways supercomputers are built is by interconnecting hundreds of microprocessors. Supercomputers are mainly used for weather forecasting, biomedical research, remote sensing, aircraft design, and other areas of science and technology. Some examples are CRAY YMP, CRAY2, NEC SX-3, CRAY XMP and PARAM from India.