Class 11 IT (Information Technology) - 1.Basics Of information Technology (Short Notes)
1. What is Information Technology (IT)?
Information Technology, or IT, simply means using computers to operate information — like to store it, find it, send it, or use it in different ways.
2. Data vs. Information
Data: Raw facts or numbers without any meaning.
Example: 16, Varad, Cricket
Information: When data is arranged or organized properly, it becomes meaningful.
Example: A boy named Varad, who is 16 years old, and likes to play cricket.
3. Parts of a Computer
There are two main types of computer:
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Hardware: The parts you can touch and see.
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Software: The set of programs that tell the hardware what to do. (We can't touch)
4. Hardware (The Body)
Input Devices: The input device are used to give instructions or data to the computer.
Examples: Keyboard, Mouse, Scanner, Microphone etc.
CPU (Central Processing Unit):
- This is called as the brain of the computer.
- It processes all data and performs calculations.
Output Devices: These show the results after processing the input.
Examples: Monitor, Printer, Speakers
Storage (Memory): This is where data and information are stored.
- Primary Memory (RAM):
- This is temporary memory — data disappears when the power is turned off.
- Volatile Memory
- Secondary Memory (Hard Disk, Pen Drive, SSD):
- This is permanent memory — data stays safe even after the power is off.
- Non-Volatile Memory
5. Software
System Software (Operating System – OS):
The main software that manages all computer activities.
Without it, a computer can’t work.
Examples: Windows, Android, macOS
Application Software (Apps):
These are programs made for specific purposes.
Examples: Google Chrome, MS Word, WhatsApp, Games.
6. Units of Memory
From smallest to largest unit:
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Bit: The smallest unit (0 or 1)
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Byte: 8 bits
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Kilobyte (KB): 1024 bytes
Megabyte (MB): 1024 KB
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Gigabyte (GB): 1024 MB
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Terabyte (TB): 1024 GB
7. Different Types of Computers
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Microcomputer: Used for everyday tasks — Desktop, Laptop.
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Minicomputer: Used for small or medium companies — supports several users.
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Mainframe Computer: Very large and powerful — used by banks, railways, and big organizations.
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Supercomputer: The fastest and most powerful — used for scientific research and weather prediction.
8. Computer Networks
When two or more computers are connected to share data and resources, it’s called a network.
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LAN (Local Area Network): Covers a small area like a home, school, or office.
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MAN (Metropolitan Area Network): Covers a city or large campus.
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WAN (Wide Area Network): Covers large distances — even countries.
9. Computer Safety and Ethics
Virus: Harmful programs that can damage your computer or steal your data.
Computer Safety : The correct way of using computers that keeps data safe.
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Don’t misuse or steal others’ data.
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Don’t install or use harmful software.
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Keep your password secret and protect your personal information.
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