What term describes a device that combines both transmitter and receiver functions?

The term that describes a device that combines both transmitter and receiver functions is "transceiver." A transceiver is a critical component in communications technology, as it enables two-way communication by both sending and receiving signals. This dual functionality is essential for various applications, such as radio communications, networking equipment, and many wireless technologies.

In essence, a transceiver effectively integrates the capabilities of a transmitter, which sends out information, and a receiver, which captures incoming information. This design allows for efficient utilization of space and resources in a device, making it particularly beneficial in wireless networks where compact and versatile devices are necessary.

The other options, while related to communication technology, do not encompass both transmitter and receiver functions in the way a transceiver does. A modem, for instance, primarily modulates and demodulates signals and is more focused on converting digital data to an analog signal and vice versa. Routers facilitate traffic management between networks rather than functioning as both transmitters and receivers. Hubs function as basic connection points within a network to distribute data but do not actively transmit and receive signals in the same integrated way as a transceiver.