Definition of Computer | Characteristics of computer |

•  COMPUTER - A DATA PROCESSING MACHINE:-

The word computer comes from the word "compute", which means, "to calculate”.

A computer is an electronic device or machine that can perform arithmetic operations like a addition, subtraction, multiplication, division etc. as well as logical operations like-comparison at very high speed. A computer is also called a "Data Processor" because it can store, and retrieve data whenever desired. The activity of processing data using a computer is called Data Processing or Electronic Data Processing (EDP). The ultimate goal of data processing is to transform data into information. It saves time, money and man power.

Data is raw material used as input and Information is processed data obtained as output of data processing.

Being a data processing system, computer has importance in providing in-depth knowledge of whatever is involved in processing the data. But before looking into that, we require to define some of the basic terms associated with it.

• INPUT :-

Input refers to the data and instructions given to the computer. Where data is a raw set of facts and figures associated with an individual, an entity, or an event. It is basically a collection of unorganized facts or concepts that does not convey any meaning. Data can be represented in various forms i.e. in figures, characters, symbols, pictures, audio, video etc. Some examples of data are phone numbers, weights, prices, costs, addresses, product name, age or name of a person etc. Instruction specifies how the data is to be manipulated. It is basically a command given to computer to carry out a particular operation on the data. In simple, instruction specifies what to do with the data. Example: 2 + 3 (Here 2 and 3 are the data, and the instruction is addition operation (+)).

• PROCESS:-

It is the actual interpretation and execution of the instruction on data, which is carried out by the computer's processing unit (microprocessor) to obtain the required result.
It is the actual interpretation and execution of the instruction on data, which is carried out by the computer's processing unit (microprocessor) to obtain the required result.

Example:

2 + 3 - 4 (Here 2, 3 and 4 is the data, and the process to be carried out is to first take out a sum of 2 and 3, and from the result of the summing process subtract the value of 4).

• OUTPUT:-

The result obtained from the process is called as an output. Computer processes the data according to the instructions fed into it and produce the required results. This result is known as output Example: In the above example stated for process (2 + 3 – 4), the output is 1.

• INFORMATION :-

Meaningful output is information. When we apply some process on data, we get some result. This result is called output. But if that output is meaningful for someone, then it becomes information for him/her. Example: The average performance of a class is derived as an output from the process of summing up all the marks of the class, and dividing it by the number of students. This output would be meaningful to the class teacher, but maybe not to the peon of the school. The output derived is information for the class teacher but not to the peon.

• KNOWLEDGE :-

Knowledge is what we know about a particular domain information. (field). It is usually based on learning, thinking, and proper understanding of the problem area. Knowledge is derived from information in the same way as information is derived from data. It refers to the use of information to make decisions.

• CHARACTERISTICS OF COMPUTERS :-
  

A computer is equipped with number of characteristics that helps it to handle the different problems more efficiently.

1. Accuracy :- Computer system always produces accurate results with valid data and instructions. In simple terms, one cannot expect correct and accurate results when the instruction set to manipulate the data is incorrect or the data which user is supplying to the computer is wrong.
   
2. Speed :-A computer performs operations with very high speed. It can process millions of instructions in fraction of seconds. The speed of a computer varies from computer .
3. Large Storage Capacity :- Computer has large storage capacity. It can store large volume of data. We can store kind of data in computer's storage. This data can be text, picture, sound, video etc.
   
4. Versatility :- Computer is a versatile machine. It can perform a number of jobs depending upon the instructions fed to it. Like a computer can be used to write a letter to a friend in a word processor and at the same time listen to various songs through a media player. The same machine (computer) works in different fields with different applications to perform various tasks. This property of computer is called versatility.
   
5. Reliability :- Computerized storage of data is much more reliable than the manual storage. We can store the data in computer's storage for a long period of time except until any kind of system failure occurs .
6. Diligence :- Unlike human beings, the computer can work continuously without getting tired. It can perform the same task repeatedly with same processing speed. Without the lack of concentration they help us in doing a number of jobs that require a great accuracy.
   
7. Automatic :-A machine that works itself without any human involvement is said to be an automatic machine. Computers are automatic machines, they can work on any given job automatically till it gets finished without any human interference.
   
8. Source of Entertainment:-Today, computer has become a great source of entertainment. We can play video games, enjoy music and watch movies or various satellite channels through computer. We can also communicate with each other through computer by means of text messages, audio/video messages .
9. Cost Effectiveness :- Computers reduce the amount of paperwork and humo example: we can create and edit student reports easily using electronic reports to management via e-mail .
   
10. No Intelligence :-computer has no intelligence of its own It depends upon user's instructions for of task. Now days, some artificial intelligence (AD) has been 1 computer to take some decisions on its own.
    
11. Health Issues :- Prolonged or improper computer use can lead to injuries or disorders of the hands, wrists, elbows, eyes, necks and back. Computer users can protect themselves from these health risks through proper workplace design, good posture while at the computer, and appropriately spaced work breaks.