Time signatures — not everything is four

A waltz and a march can share the same tempo and still feel completely different.

Not every song counts in fours. Some count in threes — the waltz with its 1-2-3 is the best-known example; others are in 6/8, which feels like two groups of three. This is called the time signature. Because the heavy beat recurs at a different interval, the effect changes even when tempo and chords stay the same.

This section stays brief: most pop, rock, and folk music is in four. Threes and sixes are worth knowing but are the exception.