In digital communications, what term is commonly misused to describe data rate capacity?

The term commonly misused to describe data rate capacity is bandwidth. In the context of digital communications, bandwidth refers to the range of frequencies that a communication channel can carry, rather than the actual data transmission rate. It is often confused with data rate capacity, but bandwidth is essentially a measure of the channel's capacity to transmit data without considering the efficiency or actual throughput that may vary based on various factors like network conditions and protocols.

Throughput, on the other hand, accurately measures the actual data transfer rate experienced by users, taking into account all delays, data collisions, and overhead. Latency refers to the time it takes for a packet of data to travel from the source to the destination and does not directly correlate with capacity. Meanwhile, signal-to-noise ratio is a measure used to quantify the level of a desired signal to the level of background noise, which affects the quality and reliability of data transmission rather than its capacity.