Which one among the following devices is used for converting digital signals into analog signals and vice versa?

A Modem (short for Modulator-Demodulator) is a hardware device used to bridge the gap between digital and analog signals. Computers process information in digital format (discrete binary code), whereas traditional communication channels like telephone lines or cable systems transmit data as analog waves.

• Modulation: The modem converts digital signals from a computer into analog signals for transmission.
• Demodulation: It converts incoming analog signals back into digital data for the computer to understand.

In contrast, other networking devices have different roles: a Router manages and directs traffic between different networks; a Switch connects multiple devices within a single Local Area Network (LAN); and a Bridge connects two separate network segments to function as a single network.