Pitch is half of music; time is the other half. Metre is the regular pattern of strong and weak beats that a rhythm sits on, and the time signature tells you which pattern a piece uses.
Pulse, beat and metre
Metre is the recurring pattern of accents, downbeats and beats. It comes from two levels of motion at once: a faster one that gives the pulse, and a slower one that groups those pulses into repeating bars. When the pulses are counted inside a bar, they are called beats.
Reading a time signature
A time signature is two stacked numbers. The upper number says how many of a given note value make one bar; the lower says which note value that is. 4/4 is four quarter notes to the bar. It is so common that it has its own symbol and name, common time. 2/2, with its own symbol, is alla breve or cut time.
| Kind | Beats grouped in | Examples | Count it |
|---|---|---|---|
| Simple | Twos | 2/4, 3/4, 4/4 | 1 & 2 & 3 & 4 & |
| Compound | Threes | 6/8, 9/8, 12/8 | 1 2 3 4 5 6, felt as two |
The most common time signatures are 2/4, 3/4 and 4/4. 6/8 holds six eighth notes, the same as 3/4, but grouped in two threes rather than three twos, so it is felt in two big beats.
Tempo
Tempo is the speed of the beat, usually measured in beats per minute. Classical scores more often give an Italian word, sometimes with a metronome mark: "Andante", walking pace; "Allegro", cheerful; "Presto", quickly. Metronome marks spread in the first half of the 19th century, after Johann Nepomuk Maelzel invented the metronome; Beethoven was one of the first composers to use it, publishing marks for his first eight symphonies in the 1810s. In electronic dance music the tempo is simply given in BPM, and DJs need it to beatmatch.
Sources
Every date, name, tempo and origin on this page comes from these pages, read on 2026-10-24.