Police hand signals
Traffic police hand signals are directed at drivers AND pedestrians together, and they override the traffic lights.
Learn the basic set: stop for traffic in front, stop for traffic behind, stop for both, go/proceed, and the beckoning signal that releases one direction at a time.
A driver may also use hand signals - to indicate slowing, stopping or a turn - which matters when an indicator has failed or on a vehicle that has none.
If you are unsure what an officer is signalling, stop and wait to be waved on. Guessing at a junction is how two vehicles move at once.