The computers that are accessible these days differ in their sizes & types. So, the computers are categorized according to the purpose, data handling, functionality. Based on the purpose, the computers may be either general purpose or specific purpose. The classification of computers usually depends on size, technology, area of application, type of data processed, etc. According to the data handling computers are classified as:
|Digital Computers||Analog Computers
||Analog + Digital|
This table shows that computers can be divided into digital, analog, hybrid & digital computers are further divided into purpose-wise and size-wise computers:
|Classification By Purpose
Classification By Size
These are the most commonly used types of computers as they are more accurate, faster, reliable. They take inputs into binary language and convert them into user understandable language. They operate on data that are demonstrated in binary code such as 0’s & 1’s (using only the two digits 0,1 also means false / true respectively). In digital computers data flows in the form of pulses.
Classification of Digital computers
Digital computers have been classified according to the needs of the user. Depending upon the purpose of use, digital computers are classified as a special purpose or general-purpose computer.
|Classification By Purpose (according to the need of the user)|
|Special Purpose Computers: These computers are designed to handle a specific problem or to perform a specific task of a specific environment and cannot be used for other purposes. It means that they do not show versatility.
General Purpose Computers: These computers are used for all general purposes of the users. They show versatility as they can perform several jobs such as calculate data, writing letters, playing games, watching movies, etc. They can be used to solve problems whenever you want. They include the following:
|Classification By Size (according to their physical size & appearance)
|Micro Computers: These are the smallest computers which are designed to perform a single microprocessor function of ALU (arithmetic logic unit) and CU (control unit) such as Desktop/Personal Computers (PC) & Laptops. 80-90% of peoples usually prefer micro-computers as they have the following features:
Mini Computers: Minicomputers are general-purpose computers, has medium power. Their capabilities lie between the microcomputer and mainframes i.e., more than the microcomputers but less than the mainframes. These are very portable, which means they can easily carry.
Mainframe Computers: Mainframe computers are used in those organizations where a large number of people periodically approach to the same data like banks-ATM transactions, ticket reservation, insurance companies, flight scheduling, etc. It is a multiple-processing system & has a large size.
Super Computers: Supercomputers are used for calculating large numbers in a very short amount of time. The computers are called supercomputers on the basis that how much the number is large & how fast a computer can calculate a large number. These computers have thousands of processors that can calculate numbers at very high speed. Supercomputers are the most powerful, expenses, fastest computers. They are big as compared to personal computers and mainly used in large business organizations. The purposes for which supercomputers are used are:
Desktop/Personal Computers: These are the personal computer that is most widely used all over the world. They can be easily fit on a desk. They are usually used to manage the personal information of an organization or a person, that’s why they are named so.
Laptop: These computers are so small that you can easily carry for use while traveling. You can easily place these type of computers on your lap as they are light in weight and tiny in size. You can easily carry your laptop while traveling and can be used anytime & anywhere without any power connection. These computers are made up of an LCD (liquid crystal display) screen. These computers are useful in various fields such as educational, organizational, homes, etc.
Embedded Computers: These computers are established or inserted inward the numerous electronic devices to perform functions. They are designed to perform a specific task like microwaves that are only used to heat or cook the food, washing machines that are designed to wash clothes, televisions are specified for entertainment, etc are the various devices that have fixed embedded computer inside them. A digital washing machine is consists of a small computer which is equipped in it to direct or manage the washing process of the machine.
Programmable Computers: Programmable computers are the computers that are self-programmed by users such as PDA (Personal Digital Assistant), mobile phones (latest technology called smartphones), address book, etc. Personal Digital Assistant is a mobile device performs functions as a personal information manager and has mobile phone functionalities like keyboard, internet connectivity, Bluetooth connectivity, calendar, calculator, touchscreen, etc. Latest mobile phones include address book for contacts, memory card for storage, contact/call list, touchscreen, web browser, etc. These computers are specialized to keep records of meetings, call lists, SMS, image & video capturing and involve Bluetooth, calculator, calendar, notepad, MP3 players, etc.
The devices that are used to measure physical quantities (such as length, height, temperature, electric current, etc) are called analog devices. The analog computers accept the data in the form of signals and then, convert them into digits or in numbers (numerical values). This technology has been used in various fields like science, engineering, industrial, business, etc. Analog computers are less because they show less accuracy as compared to the digital computers.
Example of Analog devices: Thermometer
A thermometer is unable to perform calculations even that it can measure the temperature of the body through signals.
Another examples are speedometer, stethoscope, etc.
Hybrid computers are the combination of both the above computers i.e. analog & digital computers. They have the features of both devices. Hybrid computer has the speed of analog computers and has the accuracy of digital computers. These devices are used to convert data from digital to analog and analog to digital. These devices are mainly used scientific calculation, in hospitals to measure heartbeat, etc.