Final answer:
Drum brake shoes are held against the anchor pin by springs when not engaged, preventing unnecessary friction and wear.
Step-by-step explanation:
In the unapplied position, drum brake shoes are held against the anchor pin by springs. The springs ensure that when the brakes are not engaged, the shoes are pulled away from the drum to prevent friction and wear. When the brake pedal is pressed, hydraulic pressure forces the brake shoes against the drum, creating the friction needed to slow down the vehicle. However, in the rest position, hydraulic pressure is not applied and it is the springs that hold the brake shoes back.