Pitch in music refers to how high or low a sound is.
How clefs affect pitch in music
Musical notes are how we write down the pitch in music – they tell musicians what pitch to play, when to play it, and for how long.
In written music, we can only work out what pitch a note on the stave is if there is a clef.
Most instruments have one register, high or low, so their music is written on one stave and in one clef.
Music for the flute is written in the treble clef.
Music for the cello is written in the bass clef.
Sopranos, mezzo-sopranos, and tenors sing music written in the treble clef;
and basses sing music written in the bass clef!
Piano music is written in the treble and bass clefs because the piano has many pitches.
There are other registers, too – the alto and tenor clefs. But at primary school, children only need to learn about the treble and bass clefs.