Modem – Stands for Modulator and Demodulator. Modems can be
analog (dial-up) or digital.
• Dial-up modem – Electronic devices that convert analog phone
signals into digital signals that the computer can process, and digital
computer signals into analog signals that can be transmitted over the
telephone lines. Dial-up modems can be internal or external.
• Digital modem – Used to send and receive data to and from a digital
telephone line, like Digital Subscriber Line (DSL) or Integrated Services
Digital Network (ISDN).
Network Interface Controller (NIC) – Also referred to as network adapters
or Local Area Network (LAN) adapters. They usually connect to networks
using an Ethernet cable. NICs can be internal (expansion cards or
integrated to the system board) or external
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Communication Devices