If you wondered what "Foley" is when you see it in the credits of a movie, or if you're on a production and someone says, "We'll have 'Foley' cover that", then here's a great link to give you just about all the info on the subject you'll ever need.
Foley is essentially the recorded sound of feet/footsteps, cloth/clothing moves, or specific props in a movie. 99% of the time it is recorded in sync to picture. (the artist records the moves while watching the scene) Notice the multitude of props and the variety of floor surfaces/pits in the picture. The more options a foley artist has at his/her disposal, the better the tracks will match what's on the screen.
A big difference in Foley and sound design/effects tracks is that usually the Foley tracks are meant to be more felt than heard. In most cases, if Foley sticks out, either you have a bad take or a bad mix. The point is that you want it to sound like they captured it on the set, not in a studio three months later. There are cases where Foley covers specific props that play forward in the overall mix, and that's cool - it's just not the norm.
Philip Rodrigues Singer has put together a great and informative site to educate you about Foley, starting with it's originator and first Foley artist, Jack Foley.
Here is the site:
The Art Of Foley
Go check it out. You can impress your friends the next time you go to a movie and you say, "The Foley in that movie was really well done!"