Explanation

• A Modem (Modulator-Demodulator) converts digital signals into analog signals and vice versa.
• It is used to connect computers to the internet via telephone lines or other networks.

Additional information:

• Switch – connects multiple devices in a network
• Hub – basic network connector
• Repeater – boosts signal strength
• Router – directs internet traffic

Last verified on 19-04-2026

Explanation

An email address consists of two parts: 

1. Username or ID (the name or ID chosen by the user)
2. Domain name (the name of the organization or service provider).

Format: Username@Domainname.com

Example: john.doe@example.com

Additional information:

• Email, short for Electronic Mail, has its roots in the early 1960s.
• The first email was sent in 1971 by Ray Tomlinson.
• He also introduced the "@" symbol to separate the username from the hostname.

Last verified on 19-04-2026

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

• OTP stands for One Time Password.
• It used in banking security systems.
• It is a temporary code sent to the user’s mobile/email.
• Introduced widely in digital banking for secure transactions.
• It is valid for only one login or transaction.
• Helps prevent unauthorized access and fraud.

Last verified on 19-04-2026