Updated: Aug 11
A Computer is a very multipurpose electronic machine produced by man. Computer has made a huge impact on our each day life. It is used in different fields like home, school, college, office, industry, hospital, bank, retail store, railways, research and design, organizations etc. A computer is basically a programmable computing machine. Previously computers were used for complex computing.
The word computer comes from the word compute, which means to calculate. So, a computer is normally considered to be a calculating device that can perform arithmetic operations.
A computer can not only store and process data, but also retrieve data. This means gather data from its memory or storage when needed. So we can say that a computer is a general term that refers to an electronic data processing machine which is used for a wide variety of activities.
In other words "एक कंप्यूटर एक इलेक्ट्रॉनिक उपकरण है जो कच्चे डेटा को इनपुट के रूप में स्वीकार करता है और प्रक्रिया के बाद इसे आउटपुट के रूप में परिणाम देने के लिए निर्देशों के एक सेट के साथ संसाधित करता है। यह गणितीय और तार्किक संचालन करने के बाद ही आउटपुट प्रदान करता है और भविष्य के उपयोग के लिए आउटपुट को बचा सकता है। यह संख्यात्मक और साथ ही गैर-संख्यात्मक गणनाओं को संसाधित कर सकता है | "
According to size there are different types of computers which are below:
1. Super Computers
2. Mainframe computers
3. Mini computer
4. Micro Computers
Super Computers: Super computers are the most powerful, fastest and costly computers. These are mainly projected to process bulk of data have ability of performing almost 1 trillion calculations per second. It is constituted of thousands of processors and such are perfect for large and complex problems that require great calculating power.
They are used for lots of scientific and technical together with weather forecasting and automatic design. Super computers are also being used to map the human genome or DNA structure. CRAY-3, Cyber-205 and PARAM are example of super computers.
Mainframe Computers: Mainframes are the biggest type of computers that are used in common use. It is typically slower, less powerful and fewer costly than super computers. It possesses memory capacities calculated in gigabytes and more and can execute well over 100 millions of instructions per second.
Mainframes are capable of handling several applications within a timesharing environment. Mainframe computers are used essentially in research organization, airline and railway reservations, large industrial banks etc. Mainframe can also serve like teleprocessing system with remote connection all over the globe.
Mini Computers: First time Mini computers were released in 1960’s. They were named so because of their size compared to other computers of the day. The capabilities of these computers are everywhere between mainframes and personal computers.
Mini computers are well modified for payroll preparation, accounting and scientific computation, database management, word processing, computer Aided Design, Numerical Analysis etc. They are also used for real time controls and engineering design work. PDP-11, VAX 7500, HP 3000 etc are examples of mini computers.
Micro Computers: Micro computer is known as personal computer. A micro computer is the smallest and cheap computers. Micro essentially refers to the physical size and circuitry of computer rather than its capabilities. A typical micro computer have about 64 MB of data processing speed of micro computer are calculated in megahertz instead of megahertz instructions per second. In 1981 IBM launched first micro computer which was known as IBM PC. Desktop, laptop and palmtop are known as micro computer.
Workstations: Workstations is a class of the minicomputer and microcomputer. Micro computers typically use superior processors and characteristic more RAM and storage capacity than personal computers. Workstations have large, high resolution monitors and accelerated graphics managing capabilities which make them perfect for the purpose of sophisticated design, modeling and animation etc.
According to technology types of computers.
1. Analog computer
2. Digital computer
3. Hybrid computer
1. Analog Computer: Analog computer handles or process information of a physical nature like temperature, pressure etc.
2. Digital Computer: Digital computer process information which is essentially in a two state form is called the binary. It has two numbers zero and one. There are different types of digital computers like microcomputers, minicomputers, mainframes and supercomputers.
3. Hybrid Computer: Hybrid computer are those computer which has some element of analog computer and some of digital computer. i.e. we can say that hybrid computer has both types property analog and digital computers.
Characteristics of Computers:
There are following characteristic of computers which are below:
1. Fast speed of calculations and storing of information.
2. The ability to take in information and store it for future use.
3. The ability to take a variety of instructions for execution of tasks.
4. The ability to use simple logical rules to make decisions for their internal control of for the control of some external activity.
5. The ability to communicate with other computer systems.
6. संगणनाओं को अंजाम देना और सही और तेजी के साथ विश्लेषण करना।
Anatomy of a computer:
There are 5 major functional units of a digital computer are:
1. Central Processing Unit (CPU)
2. Inputs Units
3. Output Units
4. Storage units
5. Communication interface
CPU is the brain of a computer. The other parts are used to transfer data and to communicate with the CPU. The CPU constitutes the main memory, control unit and arithmetic logic unit.
The five units are explained in below:
Inputting: It refers to the process of entering data into the computer by an input device like keyboard.
Storing: It refers to storage of data and instructions in the computer’s main memory for manipulations.
Processing: It refers to performing operations or manipulation of data entered into the computer so that useful information may be gathered from the entered data.
Output: It refers to the process of showing the information or result to the user either on screen or on paper.
Controlling: It refers to directing all the above processes in coordination. This controlling is done by control unit.
In this figure, the solid lines are used to indicate the flow of instructions and data. The dotted lines represent the control exercised by the control unit. .The figure shows the basic arrangement of the different units of the computer. These five units correspond to the five basic operations known as inputting, storing, processing, outputting and controlling data, carried out by all computer systems.
Generation of Computers
First Generation Computer
Year: 1944 to 1959
Circuitry: Vacuum Tubes
Processors: ENIAC, EDSAC, EDVAC UNIVAC, IBM
Developed by: Mauchly and Echert
Second Generation Computer
Year: 1960 to 1964
Processors: System/360, IBM, Bunch
Developed by: John Barden, William Brattain and William Shockley
Third Generation Computer
Year: 1965 to 1975
Circuitry: Integrated Circuits (IC)
Devices: Timesharing, minicomputer
Processors: PDP, System/32, System/36
Developed by: Jack Kilby
Fourth Generation Computer
Year: 1975 to 1990
Circuitry: Very large scale integration (VLSI) and the Microprocessor
Devices: Microcomputer, Embedded computer, personal computer
Processors: VAX, AS/400, Intel Motorola, MOS, Zilog, WDC, Pentium, ARM architecture, MIPS, SPARC
Developed by: Ted Hoff
Fifth Generation Computer
Year: 1990 to till now
Circuitry: Small computer System Interface (SCSI), Video electronic standard Association
Devices: Super Computers, Mainframe Computer, Mini Computer, Personal computer, Mobile Computer, Power PC, PowerMacs, Play Station
Processors: Commodore, UNIX System, Intel Pentium, Pentium MMX, Pentium 2, AMD, Athlon, Pentium 3, Pentium 4.
FAQ for Computer:
Q. What is full form of computer?
Ans. The full form of computer is Commonly Operated Machine Particularly Used in Technical and Educational Research.
Q. Who is father of computers?
Ans. Charles Babbage is known as father of Computer.
Q. How many generation of computer?
Q. What is full form of CPU?
Ans. The full form of CPU is Central processing unit.
Q. What is the full form of ALU?
Ans. The full form of ALU is Arithmetic logic unit.
Q. What is brain of computer?
Ans. CPU is the brain of computer.
Q. What is the full form of RAM?
Ans. The full form of RAM is Random Access Memory.
Q. What is the full form of ROM?
Ans. The full form of ROM is Read Only Memory.
Q. What is the full form of PROM?
Ans. The full form of PROM is programmable read only memory.
Q. What is the full form of EPROM and EEPROM?
Ans. The full form of EPROM is Erasable programmable read only memory and EEPROM is electrically Erasable programmable read only memory.
Q. What is the full form of CD and DVD?
Ans. The full form of CD is Compact disk and DVD is digital video disk or digital versatile disk.
Q. What is the full form of WORM?
Ans. The full form of WORM is Write Once Read Many.
Q. What is the full form of OMR?
Ans. The full form of OMR is Optical Mark Reader.
Q. What is the full form of MICR?
Ans. The full form of MICR is Magnetic ink character Recognition.
Q. What is the full form of OCR?
Ans. The full form of OCR is Optical Character Reader.
Q. What is the full form of CRT?
Ans. CRT is Cathode Ray Tube.
Q. What is the full form of TFT or LCD?
Ans. TFT is Thin Film Transistor and LCD is Liquid Crystal Display.
Q. What is the full form of ASCII?
Ans. The full form of ASCII is American Standard code for information interchange.