Find nth instance of a character in a string

Mod. edit: BrisbaneBob - please don't post q's in another member's thread (no matter how old it is) - post moved to dedicated thread.

This formula was offered as a method of finding the nth instance of "/" in a string. I have used it successfully. I have run it through Formula Evaluate to see how it works but I still can't figure it out. Can someone be kind enough to explain to me how it works?

=RIGHT(A1,LEN(A1)-FIND("^^",SUBSTITUTE(A1,"/","^^",LEN(A1)-LEN(SUBSTITUTE(A1,"/","")))))

Thanks and regards