The bottom number tells us the number of beats in a bar / measure.

Time signatures are written on the staff after the clef.

The duration of a crotchet is longer than a semibreve.

Music is divided into equal parts by bar lines.

A double bar line is written at the end of a piece of music.

The duration of a minim is longer than a semibreve.

When a time signature contains a 4 as the top number, it means 4 beats in each measeure/bar.

One whole note equals four quarter notes.

For quarter notes equal one half note.

Sixteen semiquavers equal two minims.

Ledger lines are used to write musical notes over or below the staff.

One dotted quarter note equals three sixteenth notes.

One crotchet rest equals two minim rests.

One dotted half note equals three quarter notes.