MATLAB: GUIDE, calling functions

guideMATLAB

Hi all, might just be me, but I am having a hard time finding som info on GUIDE that I can use, I know nothing of GUIDE, but I know how to use and do code in matlab, but my problem is how to make a GUIDE that executes a function which lies in a seperate m-file when pushing a pushbutton
and also how to run a function with parameters, when i have two textboxes and a button, still running a function in a seperate m-file.
Is this even possible? searched google and mathworks without getting a usable answer.