Computer

Lesson - 1 

COMPUTER : GENERAL INTRODUCTION 

What is Computer?

Often people think that the computer is like an almighty superman, but it is not so. It is simply an automatic electronic machine that works at high speed and makes no mistakes. Its capacity is limited. It is derived from the English word compute which means to calculate. In Hindi it is called computer. It is used to process and collect a lot of information.

• A computer is a device that receives data and processes it to produce results as per software or program.
• Computer has been termed as artificial intelligence. Its memory power is higher than that of humans.

Elementary words relating to computer.

1.Data - This is unorganized data or facts. This the stage before the process. Generally data is divided into two parts-

(a) Numerical Data : I this type of data, digits 0 to 9 are used. Like salary of employees, marks obtained in examination, censure, roll number, arithmetical numbers etc.

(b) Alphanumeric Data : This type of data consists of numbers, letters. And symbols are used like address etc.

2. Information - It is the result obtained after processing unorganized data which is organized. 

Characteristics of Computer.

1. It works at a fast speed, which means time is saved.

2. It works flawlessly.

3. It provides permanent and large storage capacity.

4. it is capable of talking rapid decisions as per pre defined instructions.

Uses of Computer.

1. In the field of education.

2. In scientific research.

3. Railway and Airlines Reservation.

4. In the bank.

5. In Medical Science.

6. In the field of defense.

7. In Publication.

8. In business.

9. Communication.

10. In Administration.

11. In Recreation.

Functions of Computer.

(A) Data collection                  (B) Data storage.

(C) Data Processing                 (D) Data output.

Data Processing & Electronic Data Processing.

Before the creation of computers, the journey of data collection processing and output to achieve a specific goal was done through manual method, which was called processing. As technology developed, computers started being used for all these tasks. This is called Electronic Data Processing (E.D.P)|

• The main goal of data processing is to obtain organized information from raw data which is used for decision making. 

                                 Input ---------------- Process ---------------- Output

                       Incoming data                                             Outgoing information

Computer System - 

It is a group of devices that together process data. Computer system consists of many units which are used in electronic data processing. The basic computer processing cycle includes input, processing, and output.

1. Input unit : 

A unit which receives data from the user and transmits it in the from of electronic pulses to the central processing unit. Like when we go for withdrawal in (Automatic Teller Machine ATM) we have to enter the (PIN) number (Personal Identification Number).

For that keypad is used as input unit. (GIGO = Garbage in garbage out) is a concept in computer science which states that the accuracy of output depends on the accuracy of input.

2. Central Processing Unit (CPU) :

It is also  called processor.. It is an electronic microchip that processes data by converting it into Information. It is called the (Brain of the computer) it controls all the functions of the computer system and converts input into output converts. It makes this like this main memory.

                                                               Central processing Unit 

                           Input unit -------------- Arithmetical logic Unit ---------- Output unit                                

                                                                     Control Unit

                                                                     Main memory   

(A) Arithmetic Logic Unit Or (ALU) - 

It is arithmetical and logical. Multiplication and division etc. and so that either Yes Or No etc. Come under the Calculation.

(B) Control Unit -

It coordinates the operation of the computer and all the parts of the computer like input output activities.

(C) Memory Unit-

It stores data. It is mainly divided into two categories. Primary and secondary memory. That is, it contains the currently used data and instructions (Register). Secondary memory is used to store sub-instructions for later.

(D) Output Unit -

The unit which takes data to the central processing unit. Makes it understandable to the user. As so we get a receipt, which is an output device from the printer. Is output device.