As you remember from the Dos and Windows 3.1 times, programming in Assembly language has always been a tough job, we had to cope with numerous nameless interrupts' services, dealing with segments, code and data size limits and so on and so on.

Things have greatly changed ever since. With introduction of Windows'95 and a flat memory addressing mode a programmer's life became easier. Much easier, to be honest. No more segments, no more interrupts. It's possible to use plain Windows API. You won't believe me, but it's even easier than C and a way more powerful, giving you total control of your program, resulting in extremely fast, compact and robust applications (heh, as they could be, relying on the Windows'95 base). It seems to me that Microsoft doesn't want us to have such a powerful tool, so it's going to be hard to find comprehensive documentation on the subject.

Below you can see an example of the 'Hello World' program, written for MASM:

;===========================================================
      .386
      .model flat, stdcall
      option casemap :none

      include \masm32\include\windows.inc
      include \masm32\include\user32.inc
      include \masm32\include\kernel32.inc

      includelib \masm32\lib\user32.lib
      includelib \masm32\lib\kernel32.lib

    .data
	szMessage db "Hello World!",0
	szTitle	db "Win32 Assembly",0
    .code

start:

     invoke MessageBox, 0,addr szMessage,addr szTitle,
	MB_OK or MB_ICONINFORMATION
     invoke ExitProcess, 0

end start
;===========================================================