Basics of Computers
Computer is a device that transforms data into meaningful information. Data can be anything like marks obtained by you in various subjects. It can also be name, age, sex, weight, height, etc. of all the students in a class.
A computer is a programmable machine. It allows the user to store all sorts of information and then ‗process‘ that information, or data, or carry out actions with the information, such as calculating numbers or organising words.
Computer can also be defined in terms of functions it can perform. A computer can i) accept data, ii) store data, iii) process data as desired, and iv) retrieve the stored data as and when required and v) print the result in desired format.
Mainframe computers are large-sized, powerful multi-user computers that can support concurrent programs. That means, they can perform different actions or ‗processes‘ at the same time. Mainframe computers can be used by as many as hundreds or thousands of users at the same time. Large organisations may use a mainframe computer to execute large-scale processes such as processing the organisation‘s payroll. Mini-computers are mid-sized multi-processing computers. Again, they can perform several actions at the same time and can support from 4 to 200 users simultaneously. Workstations are powerful, single-user computers. They have the capacity to store and process large quantities of data, but they are only used by one person at a time.
All the components of Computer can be classified as:-
- Input Unit: This unit is used for entering data and programs into the computer system by the user for processing. b. Storage Unit: The storage unit is used for storing data and instructions before and after processing. c.Output Unit: The output unit is used for storing the result as output produced by the computer after processing. d.Processing: The task of performing operations like arithmetic and logical operations is called processing. The Central Processing Unit (CPU) takes data and
instructions from the storage unit and makes all sorts of calculations based on the instructions given and the type of data provided. It is then sent back to the storage unit. CPU includes Arithmetic logic unit (ALU) and control unit (CU)
Input devices accept data and instructions from the user. For Example 1. Keyboard 2. Mouse 3. Light Pen 4. Optical/magnetic Scanner 5. Touch Screen 6. Microphone for voice as input 7. Track Ball
Output devices return processed data that is information, back to the user. Some of the commonly used output devices are:
- Monitor (Visual Display Unit) 2. Printers 3. Plotter 4. Speakers
Software is the computerised instructions that operate a computer, manipulate the data and execute particular functions or tasks.
Programming language: An artificial set of rules, vocabulary and syntax used to instruct the computer to execute certain tasks.
Computer program: A sequence of instructions that can be executed by a computer to carry out a process.