The Bass Clef & Ledger Lines
The treble clef's other half — how the bass clef names its lines and spaces, and how ledger lines carry notes beyond either stave.
Explainer
You already know the treble clef, used for higher-pitched instruments and a pianist's right hand. The bass clef (or F clef) does the same job for lower pitches — a pianist's left hand, cellos, bassoons, trombones and more.
On the bass clef the lines, bottom to top, spell G B D F A — remembered as "Good Boys Deserve Fruit Always". The spaces, bottom to top, spell A C E G — "All Cows Eat Grass".
The bass clef's curl wraps around the F line (the second line from the top) — the two dots, one above and one below that same line, confirm it.
Middle C sits just above the bass stave, on one ledger line — the exact mirror of where it sits below the treble stave. Both clefs are simply two windows onto the very same continuous set of pitches.
Worked examples
The five bass-clef lines
Bottom to top: G, B, D, F, A.
The four bass-clef spaces
Bottom to top: A, C, E, G — spells ACEG.
Middle C, above the bass stave
Middle C sits just above the bass stave, on one ledger line — the mirror image of its spot below the treble stave.