SAT Eassy VS GMAT Argument Eassy

Hi, there;

I just read the SAT writting book yesterday;  and now i do feel that SAT's Essay is so similar to GMAT's Argument.    however, i'm new to it.  if anyone knows  " the difference between SAT ESSAY and Arugment Essay of GMAT", i would love to get to know your experience.

thanks in advance

waiting