yes, of course there is!
a fry pan is deeper.
both are sized from 8 to 14 inches round, but skillet is only 1.5 to 3 inches deep. a fry pan is 3 to 5 inches deep (the larger 14 inch ones are close to 5 inches--smaller ones are deeper than skillets, but not ss deep as sause pans (or pots!)

you can fry bacon in a skillet, but not chicken.. well not safely!

the low sides of skillet mean you can use it for eggs, and get a flat spatula or pancake turner easily into the pan and flip the eggs (over easily)
the high sides of fry pan would make that very awkward to do.