Treble clef
The G clef on the second line.
What it means
The treble clef is the G clef on the second line from the bottom: there lies the g above middle C. It is the most frequently used clef of all and mostly the first one learned. From its single reference note, the entire remaining tonal space of the staff results.
In the notation
The sign developed from the letter G; its core is the spiral, whose centre encloses the designated line. The five lines carry, from bottom to top, the notes E, G, B, D, and F above middle C; the four spaces F, A, C, and E. Middle C lies on the first ledger line below the staff — the point where, in piano notation, the two staves meet. A small 8 below the clef means that it sounds an octave lower than written; the tenor voice in the choir and the guitar are notated this way.
Musical use
Violin, flute, oboe, clarinet, trumpet, horn, the high voice types, and the right hand at the piano notate in the treble clef. Instruments with a wide range change into it when sustaining a high register: the cello and the bassoon leave the bass or tenor clef for this. Together with the bass clef it forms the system on which the whole of modern notation rests.
The treble clef is to be distinguished from the G clef as an umbrella term — in today's practice, both words almost always mean the same sign, because the G clef now occurs only in this one position.
Other names
G clef is the umbrella term: the sign fixes the position of the g above middle C. On the second line it yields the treble clef, on the first the French violin clef of the Baroque period. With a small 8 below it, it designates octave transposition downward, for instance for guitar and tenor voice.
Performance practice
Read via anchor notes rather than via mnemonics: the g above middle C on the second line, the c'' in the third space, and middle C on the ledger line below suffice to grasp everything else as a distance. Practise recognizing intervals in the notation — line to next line is a third — so that leaps do not have to be deciphered note by note. And when you learn a second clef, practise both in separate short units rather than alternating within one exercise.