Final answer:
A circuit that selects one output from several inputs is called a digital multiplexer, which is crucial in communication systems and integral to integrated circuits in computers and smart devices.
Step-by-step explanation:
The type of circuit that takes several inputs and their respective values to select one specific output line is known as a digital multiplexer (often shortened to mux). A multiplexer serves as a data selector that channels the input from multiple lines into a single line. An important application of multiplexers is in communication systems, where they are used for combining multiple data streams into one signal for more efficient transmission over a shared medium. These devices are fundamental components in digital circuits and found within integrated circuits, also known as microchips, that form the backbone of computers and smart devices.