Delhi Public School

Sector-IV, B.S.City

NOTE: All work to be done in a thin copy .

SUBJECT: COMPUTER CLASS VI Date: 05.05.2020

WHAT IS A COMPUTER?

A computer is an electronic device that can accept instructions and input data and can manipulate that data to produce a meaningful output.

The functions of a computer are as follows : INPUT →PROCESS →STORAGE →OUTPUT

WHAT IS A COMPUTER SYSTEM? A computer system consists of input devices, central processing unit(CPU)and output devices.

BLOCK DIAGRAM OF COMPUTER

INPUT DEVICES

Input is data or instruction that you enter into memory of the computer. Input devices are used to load input data or programs

or commands and user responses into a computer. Some common examples of input devices are

1. KEYBOARD

2. MOUSE

3. JOYSTICK

4. LIGHT PEN

5. MICROPHONE.

MOUSE KEYBOARD

MICROPHONE JOYSTICK

LIGHT PEN

PROCESSING DEVICE The CPU is where the processing of the information takes place. It is the brain of the computer system. It carries out the basic instructions that operate the computer. It consists of electronic components called chips. The CPU has three parts:

1- Control Unit(CU)

2- Arithmetic Logic Unit (ALU)

3- Memory unit (MU) 1- CONTROL UNIT(CU)

● It co-ordinates and controls the activities of the computer system.

● It is also responsible for timing of all the operations done in CPU.

● It tells the computer what to do.

2- ARITHMETIC AND LOGIC UNIT(ALU)

● This is where the calculations are done(add,subtract,etc.)

● It is also where the decisions are made based on comparisons.

● The ALU has a space called accumulator where data items can be stored during processing.

● It uses logic operators example >,<,=, AND, OR etc.

3- MEMORY UNIT(MU)

● It refers to the storage space in computer.

● It stores the data temporarily for processing.

● It is used to store data, instructions and information.

● Its unit is measured in bytes.

OUTPUT DEVICES

An output device is a part of the computer system which is used to show results. Some commonly used output devices are

1. MONITOR(VDU)

2. PRINTER

3. SPEAKER etc.

PRINTER SPEAKER

MONITOR

CPU

Do as directed

1. Fill in the blanks

a. Data or instructions that you enter into the memory of the computer is_____.

b. Monitor is a ______device.

c. Full form of CPU is ______.

d. ALU is a part of ______.

e. ______co-ordinate and controls the activities of computer system.

2. Answer the following questions.

a. What is computer?

b. Write the function of computer.

c. Write difference between Input device and output device with example.

d. What is CPU?

e. Explain all three parts of CPU.