Answer

Baud rate is the number of signal symbols transmitted per second over a communication channel. Its unit is baud (symbols/second).

Important distinction

Baud rate is not always the same as bit rate. If each symbol carries more than one bit, then:

$\text{Bit rate} = \text{Baud rate} \times \text{bits per symbol}$

For example, if one symbol represents 2 bits and the baud rate is 1000 baud, the bit rate is 2000 bits/s.

Exam-ready: Baud rate = number of signal symbols transmitted per second.