Rock Around The Clock by Bill Haley & His Comets is in A at 180 beats per minute and runs 0:49 across 19 bars. It uses 8 chords — A, N.C., E7, D9, E9, D, Dm, E. The chord diagram changes as the song plays and the words light up as they are sung, so you can strum and sing along without reading ahead.
Want the melody line note by note? Rock Around The Clock guitar melody tab.