Traffic patterns are used as a general flying technique and are used a lot in training. The pattern consists of 4 "legs" called in sequence:
-SAS081 turn 140 degrees for base
This designates that you are on the last turn before entering final approach and you can accordingly set speed and flaps to match that stage of flight.
Knowing your traffic patterns greatly enhances your ability to also manage visual, circling, etc procedures and when this technique is in your back of your head you are ready to go out and fly the aircraft.
* Turkish Virtual Education Department.