A glitch is a short pulse resulting in an undesired result in a digital circuit.

All flip-flops in an asynchronous counter change states at the same time.

The modulus of a counter is the actual number of states in its sequence.

The concept of a counter to implement a digital one-shot using HDL is not used.

A J-K flip-flop excitation table lists the present state, the next state, and the J and K levels required to produce each transition.