Explanation

• DOS stands for Disk Operating System.
• It is an early type of computer operating system used to manage files and programs.
• It works through text-based commands (command line).
• A famous example is MS-DOS used in early PCs. 
• Dennis Ritchie is the father of MS-DOS.
• It was developed in 1982.

Last verified on 19-04-2026

Explanation

• PNG, JPEG, and GIF are image file formats used to store pictures.
• They are widely used in websites, graphics, and digital media.
• Each format has different compression and quality features.
• JPEG is best for photos.
• PNG for high-quality images.
• GIF for animations.

Last verified on 19-04-2026

Explanation

• F5 key is used to refresh or reload a web page.
• It updates the page to show the latest content.
• Commonly used in browsers like Google Chrome and Mozilla Firefox.

Additional information:

• Ctrl + R → Refresh page
• Ctrl + Shift + R → Hard refresh (clear cache)
• F11 → Full screen mode
• Ctrl + T → Open new tab
• Ctrl + W → Close current tab

Last verified on 19-04-2026

Explanation

To find the decimal equivalent of the binary number 1011:

(1 × 2³) + (0 × 2²) + (1 × 2¹) + (1 × 2⁰)

= (1 × 8) + (0 × 4) + (1 × 2) + (1 × 1)

= 8 + 0 + 2 + 1

= 11

Last verified on 12-04-2026

Explanation

• Spreadsheet software is used for calculations and data organization.
• MS Excel is a widely used spreadsheet program.
• It works with rows, columns, and formulas.

Last verified on 11-04-2026

Explanation

The OSI (Open Systems Interconnection) model has seven layers

1. Layer 7: Application Layer – User interface and network applications (e.g., HTTP, FTP).
2. Layer 6: Presentation Layer – Data formatting, encryption, and compression.
3. Layer 5: Session Layer – Managing sessions between applications.
4. Layer 4: Transport Layer – End-to-end connections, flow control, and segmentation (e.g., TCP, UDP).
5. Layer 3: Network Layer – Logical addressing and routing (e.g., IP).
6. Layer 2: Data Link Layer – Physical addressing (MAC addresses) and error detection.
7. Layer 1: Physical Layer – Raw data transmission over physical media (cables, radio waves)

Last updated 15-feb-2026

Explanation

The size of information in the computer is measured in: 

• 1024 kilobytes (KB) is equal to 1 megabyte (MB).
• One Megabyte (MB) = 1024 Kilobytes (KB
• One Gigabyte (GB) =  1024 Megabytes MB
• One Terabyte (TB)= 1024 gigabytes (GB).

Explanation

• Information: Data processed and organized to be meaningful.
• Data Processing: The action of converting raw data into meaningful information.
• Tabulation: A specific, structured form of arranging data in rows and columns.

Explanation

Explanation

TCP stands for Transmission Control Protocol.

IP stands for Internet Protocol.