What role does a multiplexer play in digital circuits?

A multiplexer, often referred to as a "mux," plays a critical role in digital circuits by combining multiple input signals into a single output line based on the selection lines provided. This ability allows for efficient use of resources and enables the transmission of multiple data signals over a single line, simplifying circuit design and reducing the number of required pathways. The selection lines determine which input is conveyed to the output at any given time, enabling dynamic switching between different data sources.

Multiplexers are widely used in various applications, including data routing, signal selection, and resource sharing among different components within a digital system. For instance, in a communication system, a multiplexer can facilitate the combination of several data streams (like audio and video signals) into a single stream for transmission over a network, thus optimizing bandwidth utilization.