Which two types of clefs are most commonly used?

The treble clef and bass clef are the two most commonly used clefs in music notation, covering a wide range of instruments and vocal types. The treble clef is typically used for higher-pitched instruments such as violins, flutes, and clarinets, as well as for the higher parts in choral music. It is also the clef most often used for notating melodies and themes in Western music.

The bass clef, on the other hand, is employed for lower-pitched instruments like the cello, bassoon, and tuba, as well as the lower vocal ranges in choral settings, including bass and baritone parts. Together, these two clefs encompass a vast array of musical literature and are integral to both performance and composition across many genres.

While other clefs, such as alto and tenor clefs, serve important purposes, they are used less frequently in general music practice. The soprano, contralto, and various other clefs may also have specialized uses, but the prevalence and familiarity of the treble and bass clefs make them the primary clefs for most musicians.