Computer is an electronic data processing device which accepts and stores data input, process the data input, and generates the output in a required format. Computer converts data into information with the help of a set of programs.
Computer functions in the following ways:
Input ----> Store ----> Process ----> Output
Working of computer
1. Input : Computer input is whatever is entered or fed into a computer system. Input can be supplied by a person by using a keyboard, mouse or by another computer or device such as a pen drive or CD-ROM. Some examples of input include the words and symbols in a document, numbers for a calculation, and instructions for completing a process, pictures, and so on.
2. Store : A computer must store data so that it is available for processing. Most computers have more than one devices for storing data like Hard disk, Tapes, CDs/DVDs, Pen drive etc. The storage of data in the devices that are always connected to computers like harddisk is called online storage while the storage of data in the devices that are not always connected to computers like Tapes, CDs, Pendrives etc is called offline storage.
3. Process : Data is processed to generate information. Data processing is the activity of performing calculations on data or it is simply the rearrangement of data.
4. Output : Computer output is information that has been produced by a computer. Some examples of computer output include reports, music, graphics, pictures, etc.
Characteristics of computer:
Computer has changed human life dramatically due to following characteristics :
1. High speed: Computer is a fast device which has units of speed in microsecond, nanosecond, and even the picoseconds. It can perform millions of calculations in a few seconds as compared to man who need to spend many months or years for doing the same task. Speed of computer are measured in MIPS (Millions Instruction per Second).
2. Accuracy: Computer are very accurate. The calculations are error free if input are given correct. It gives false output only when wrong data is entered. This is known as GIGO (Garbage in Garbage out).
3. Storage Capacity: Storage is a very important characteristics of computers. It can store large amount of data. It can store any type of data like images, videos, audio and many more. Today hard disks are availablein hundreds of Giga Bytes (GB).
4. Diligence: Computer is free from tiredness, lack of concentration. It can work continuously without any error and boredom. It can do repeated work with same speed and accuracy.
5. Versatility: Computer is a versatile machine which is capable of performing almost any kind of task. This machine can be used to solve the problems related to various fields. It may solve a complex scientific problem and also it may be playing a card game and so on.
6. Automatic: Computer is an automatic machine which has the ability to perform the given task automatically. Once a data and program is given to computer and stored to computer memory, the program and instruction can control the program execution without human interaction. It does not require any help from the user to process it.
7. No intelligence: A computer is a machine that has no intelligence to perform any task. Each instruction has to be given to computer. A computer cannot take any decision on its own.
Applications of computer:
Some application areas of computer are :
1. Education and research: The computer has provided a lot of facilities in the education and research. Computer based education involves control, delivery, and evaluation of learning. It is used to prepare manuals, prepare a database about performance of a student and analysis is carried out on this basis. Even distance learning is made productive and effective through internet and video-based classes. Researchers have massive usage of computers in their work from the starting to till the end of their scholarly work. They use computers for doing analysis, preparing research reports, etc.
2. Business and Industries: Computer has high speed of calculation, reliability, accuracy which made useful in all business organization and industries. It is used in business for Payroll calculations, Sales analysis, Managing employee database, etc.
3. Science and Engineering: Computers are widely used in scientific calculations and engineering purpose. One of major ares is CAD (Computer aided design) that provides creation and modification of maps and sketches of buildings, cars, etc.
4. Insurance: Computer are used to keep all records up to date with the help of computers. Insurance companies are maitaining a database of all clients with information showing procedure to continue with policies, starting date of the policies, next due installment of a policy, maturity date, calculating bonus, etc
5. Banking: In this days, bank totally depends on computer. Computer are being used by the financial institutions like banks for different purposes. The foremost important thing is to store information about different account holders in a database so that it will be available at anytime and is accessible from anywhere. Computers are also used for keeping the records of the cash flow, giving the information regarding your account, etc.
6. Health care: Computers are used in hospital and labs to keep the record of patients and medicines. It is also used in scanning and diagnosing different diseases. CT scans, Ultrasounds, ECG etc are also done by computerized machines.
7. Military: Computers are used in defence. Modern tanks, missiles, weapons etc also employs computerized control system. Some military areas where a computer has been used are: Missile control, Military communication, etc.
8. Entertainment: Computers are now the major entertainers and the primary time pass machines. We can use computers for playing games, watching movies, listening to music, etc.
Capabilities of Computer:
1. Computers can do task that are critical and dangerous and hazardous to human beings.
2. Computers have solved out problem of audio-visual problem - use of multimedia. It can be used as entertainment medium as well as educational tools.
3. Computers that are present in society has dared to undertake new activities in various fields and to function more effectively.
4. Computers perform computation in unmatched speed that too with 100 % accuracy.
5. Computers provide us information that we can use it in decision making.
Some important questions related to this chapter:
1. Define computer?
2. What are the capabilities of computer?
3. What are the major applications of computer? Explain.