The Grand Staff consists of an upper staff and a lower staff. Each staff consists of five lines and four spaces and each staff has a fancy symbol at the beginning called a clef.
Two clefs are commonly-used to write piano music: the G-clef and the F-clef.
The clef tells us which notes (by letter name) go with each line and space.
The G-clef tells us which note is G above middle C…
The G-clef is also called the treble clef because it is used to notate music for higher-pitched instruments like the female voice and violin.
The F-clef tells us which note is F below middle C…
The F-clef is also called the bass clef because it is used to notate music for lower-pitched instruments like the male voice, tuba, and bass guitar.
A Few More Words about Clefs
Important: Although the right hand is most often written using the G-clef (and the left hand in F-clef), there are occasions when the left hand plays notes written in G-clef and vice versa.
An example of left hand playing in treble clef (Clementi Sonatina)…
An example of the right hand playing in bass clef (Beethoven’s “Moonlight Sonata”):