Who can summarize how the Schengen visa works for an American?
Keeping it simple then yes, as long as you get the multi-entry Schengen visa (and yes you can see the different types on Wikipedia) then you are free to enter & exit the Schengen zone as many times as you wish So yes you can go to Croatia and return to France (so long as you have the correct documentation to any country you exit to, which you can check, but as an American the vast majority in Europe you can visit anyway)
