A clef anchors the staff. The treble clef (๐) fixes the second line as G4; the bass clef (๐ข) fixes the fourth line as F3. Every other line and space is worked out from that one anchor by running through the alphabet.
Both symbols are stylized letters, and both still point at the line they define. The treble clef is an ornamental G whose spiral curls around the second line; the bass clef is an ornamental F whose two dots sit either side of the fourth line.
The treble spiral curls around line two โ that line is G4.The two dots straddle line four โ that line is F3.
One anchor is enough; everything else is counting. Lines and spaces alternate, and the names cycle C D E F G A B. Learning one line beats memorizing a mnemonic per staff: get a mnemonic wrong and nothing tells you, get the anchor wrong and the very next note refuses to fit.
The five lines of the treble staff, bottom to top.
Common questions
How do you read the bass clef?
Start from the F line between the two dots and count by letter. The lines from bottom to top are G, B, D, F, A and the spaces are A, C, E, G. Middle C is the first ledger line above the staff.
Why does piano music use two clefs?
A piano covers over seven octaves, far more than one staff can show without a pile of ledger lines. Two staves joined by a brace split the range near middle C, so each hand reads mostly inside its own staff.