cellular modem
A device that adds cellular connectivity to laptops, desktop computers and various tablets. Typically available as an external USB module, for desktop computers, the modem may also be available on a PCI Express (PCIe) card that plugs into an empty slot on the motherboard. For older laptops, modems were available for ExpressCard or PC Card/CardBus slots.
Known By Many Names
A cellular modem via USB is a "USB modem." On a card, it can be an "air card," "data card" or "broadband card." Generic terms are broadband adapter, broadband modem, cellular adapter and 3G, 4G or 5G modem.
Alternatives: Smartphones and Routers
While a cellular modem plugs directly into the computer, smartphones and broadband routers convert cellular signals into a Wi-Fi hotspot to connect to nearby devices. See cellular hotspot and mobile broadband router.
An Internet "Stick"
Connecting via USB, this Verizon modem adds 3G CDMA cellular data service to a computer or tablet. (Image courtesy of Verizon Wireless.)
A Hotspot and Tethering
This Android Galaxy Note 3 smartphone provides cellular data service by becoming a hotspot or by cabling directly to a computer via USB (see tethering). Older cellphones were occasionally used as dial-up modems for a computer.