The Bo Diddley beat — "shave-and-a-haircut, two bits" on a tremolo guitar. Its rhythm is exactly the 3-2 son clave: three hits in bar 1 (1, the and of 2, 4) and two in bar 2 (2, 3), which is why this pattern is tagged with the son-clave cell — the same rhythm that organizes Cuban son, arriving in Chicago rhythm and blues by way of hambone and New Orleans.
How it sits: the guitar strums every eighth, but only the five clave strokes ring (downstrokes, accented); the rest are muted scratches, so the clave emerges from a continuous wash. Floor tom doubles the clave, maracas keep straight eighths, the bass holds the root on the clave hits. One chord — the groove is the song.
Listen for the silence on beat 1 of the second bar; that empty downbeat is what makes it swing.
Practice: strum muted eighths and let only the clave strokes open up.