A baud is a unit that measures the signaling rate of a line. It is the switching speed, or number of transitions (voltage or frequency change) made per second. At low speeds bauds are equal to bits per second (bps); e.g., 300 baud is equal to 300 bps. However, one baud can be made to represent more than one bit per second. The unit was first used in the late 1920s and applied to telegraphy; it is named after the French inventor Jean Baudot.