Introduction to Computer System

Introducing Computer System – Notes

1. Computer

A computer is an electronic device that works according to given instructions and performs many types of tasks quickly and accurately.

2. Uses of Computer

Computers are used in many places:

1. At Home

Drawing pictures, Typing letters, Making assignments, Paying bills, Booking tickets, Listening to music

2. At Shops and Malls

Storing list of items, Preparing bills

3. At Schools

Typing circulars and question papers, Preparing timetables, Maintaining fee records, Teaching with videos and animations

4. At Offices and Banks

Sending and receiving emails, Maintaining records

5. At Railway Stations and Airports

Checking arrival and departure time, Seat booking information

6. In Hospitals

Maintaining patient records, Medical tests and reports

7. In Scientific Research

Launching satellites, Weather forecasting

3. Characteristics of Computer

A computer has many special features:

1. High Speed – Works very fast

2. Large Storage – Stores large amount of data

3. Automation – Repeats tasks automatically

4. Accuracy – Gives correct results

5. Never Gets Tired – Works continuously

6. Communication – Helps send emails and messages

7. Entertainment – Movies, games, music

4. Hardware

Hardware are the parts of the computer that we can see and touch.

Examples: Keyboard, Mouse, Monitor, Printer, Hard disk

Types of Hardware:

1. Input Devices  2. Output Devices  3. Processing Device  4. Storage Devices

5. Input Devices

Input devices are used to enter data into the computer.

Examples:

Keyboard – Used for typing

Mouse – Used to point and select

Microphone – Used to record sound

Scanner – Used to copy pictures or documents

6. Processing Device:

The Central Processing Unit (CPU) is the brain of the computer.

It processes data and gives output.

Parts of CPU

1. Memory Unit – Stores data and instructions

2. Control Unit (CU) – Controls all operations

3. Arithmetic Logic Unit (ALU) – Performs calculations and logical operations

7. Output Devices:

Output devices show the result of processing.

Examples:

Monitor – Displays output (Soft Copy)

Speakers – Produce sound

Headphones – Listen to sound privately

Printer – Prints output on paper (Hard Copy)

Projector – Displays images on large screen

8. Storage Devices:

Storage devices store data for future use.

Examples:

Hard Disk – Main storage device inside CPU

CD (Compact Disc) – Circular disc for storing data

DVD (Digital Versatile Disc) – Stores more data than CD

Pen Drive – Small portable storage device

9. Software

Software are programs or instructions that tell the computer what to do.

Software cannot be seen or touched.

Types of Software:

1. System Software

It controls the computer and runs the system.

Examples:

Windows, Android, Ubuntu, iOS

2. Application Software

Software used to perform specific tasks.

Examples:

MS Word – Word processing

MS Excel – Spreadsheet calculations

MS PowerPoint – Presentations

Games – Entertainment

VLC Media Player – Playing music/videos

Solutions:

A. Tick (✓) the correct answer:

1. Brain of computer

✔ CPU

2. Helps to move or select icons

✔ Mouse

3. Hardware can be categorized in

✔ 4 ways

4. Which is software?

✔ OS

5. Storage device inside CPU box

✔ Hard disk

B. Fill in the blanks

Words: emails, automation, animations, shops, presentations

1. Computer can be used in automation of the steps that have to be performed again and again.

2. At offices, computers are used to send and receive emails.

3. At shops, computers are used for generating bills.

4. Computers are used to create presentations and animations using which students can learn new concepts in a fun manner.

C. True / False

1. A scanner is an input device.

✔ True

2. A CPU is made up of three parts.

✔ True

3. A computer can run without an operating system.

✘ False

4. Spreadsheets and word processors are examples of application software.

✔ True

D. Answer the following questions

1. What are internal storage devices? Give an example.

Internal storage devices are storage devices present inside the CPU box.

Example: Hard disk

2. How is hardware different from software?

Hardware: Physical parts of computer that we can see and touch.

Software: Programs or instructions that tell the computer what to do.

3. What is the difference between a CD and a DVD?

CD: Stores less data.

DVD: Stores more data than CD and is used for movies.

4. Why is the CPU called the brain of a computer?

CPU is called the brain because it controls all operations and processes all data in the computer.

5. Define application software. Give examples.

Application software is software designed to perform specific tasks.

Examples:

MS Word, MS Excel, MS PowerPoint