BJJ and judo both derive from the Japanese samurai martial arts, so many of the moves are very similar or exactly the same.

Scoring in judo is more about getting the opponent to the ground, while in BJJ it's more about positional dominance, so there is a difference in focus of the techniques.

Leg locks and shoulder locks are not allowed in judo, but you rarely see those used anyway. Arm bars, chokes, wrist and elbow locks, are all used in judo.