Modem

Modem is short for “modulate/demodulate”. It's a device that can send and receive the signal from your internet service provider and translates it for use on your local area network to access the internet.

It is commonly used in reference to a cable modem, DSL modem, or cellular modem. In mobile internet, we most often are referring to cellular modems that are built into smartphones, mobile hotspot devices, and routers.