An easy case would be dress shoes hitting a hard floor...
Each tap will consist of a few up-and-down waveforms, which can look like anything ranging from noise to a sine wave. There may be a sound when the heel hits, and another when the toe portion hits a fraction of a second later.
The taps will be separated by a period of silence, generally between 0.3 and 1 second.
A step may create more than one tap: (1) when the shoe scuffs the floor in mid-stride, and (2) when the shoe lands.