I'm making the jump from NASM to FASM since about everyone I know in assembly programming is saying it's alot better. I read the documentation for FASM and looked at some examples of Window API calls and my questions are this...

1. I use the 'invoke' 'directive?' to call an API function? Or instead of using that, do I need to tell FASM to use __stdcall and push my parameters onto the stack in reverse then call the function?

2. I use 'import' to import a library or dll?

3. I noticed that the examples have PE GUI, what exactly does this mean?

Sorry about all the questions but I have mainly been learning 16bit programming. Thanks in advance.

1) invoke is a macro, that will create the standard call for you pushing the arguments in reverse

ie invoke display,hello,world
is
push world
push hello
call display

2) a dll yes, new versions of fasm allow you to just 'reference' the dll with import macro, only functions used will be referencedin your exe - see the examples in the fasm package for windows

3) this basically formats the source as a windows portable executable file, using gui interface instead of console/command line interface. you should use "format PE GUI 4.0" to have a modern gui in your apps instead of the old flat windows like win95 (win98 onwards is where the 4.0 comes from) if you dont specify any formatting, fasm will create a flat binary file

Actually it was Win95 that was 4.0 - the earlier ones with flat (and white by default) window style were Windows 3.11 and NT up to 3.51.

ah true, thanks for pointing that out