How do brake pads return to their rest position?

OK this might be a dumb question, but...

I fitted a new set of disks and pads today (only one side so far, as its was freezing and chucking it down ), and I was surprised that there didn't seem to be an obvious mechanism that returns the brake pads to a resting position away from the disk once the piston has retracted (i.e. when you take your foot off the brake peddle).

The pads, as you all probably know, clip into the carrier using spring clips. It's obvious that the piston squeezes them together, but not the reverse.

Am I missing something? How does this work?

its just the presure released off the piston then the pads dont have any presure on them

have a look at the link below it might help it helped me when i was a collage

auto.howstuffworks.com/auto-parts/brakes/brake-types/brake.htm

vitara_mad wrote: its just the presure released off the piston then the pads dont have any presure on them

OK, so it really is that simple

The piston seals are square section.
When the brake is applied they stretch and twist slightly as the piston comes out.
Without the pedal pressure the seals relax and pull the pistons back a tiny fraction, allowing the pads to rattle off the disc as it wobbles slightly.

Are fitting new discs and pads relatively easy to do or not? I'm going to give them a go in the week if I get a dry evening.