Why is it called a WORD. And what do they mean by taking the LOWORD and HIWORD? I always wanted to know.

A WORD typically means 2 bytes.
[EDITED]: LOWORD is a macro that extracts the lower two bytes of a 32-bit value (DWORD).
HIWORD is a macro that extracts the higher two bytes of a 32-bit value.

Example:

11111111 00000000 00000000 11111111
----(HIWORD)-----------(LOWORD)-----

Dire Wolf
direwolf@digitalfiends.com

EDIT: In a fit of delusion and tiredness, I made the mistake of saying that LOWORD and HIWORD represent the first and second byte of a WORD. Duh! My mistake, I wasn't paying attention when I typed the answer (hey it was a hard day).

SiCrane posted what I really meant (see below ) .

Edited by - Dire.Wolf on December 15, 2000 12:17:58 PM

WORD is a hold over from the days when the x86 had 16 bit register sizes. A word on a processor is typically the register width. Properly a word should now be considered 32 bits, after the 386 extended the registers, but for backwords compatibility reasons, it remains 16 bits.

LOWORD is a macro to extract the low-order word of a DWORD.
LOBYTE is a macro to extract the low-order byte of a WORD.
HIWORD is a macro to extract the high-order word of a DWORD.
HIBYTE is a macro to extract the high-order byte of a WORD.

So if you have the DWORD 0xdeadbeef, HIWORD(0xdeadbeef) would be 0xdead and LOWORD(0xdeadbeef) is 0xbeef. HIBYTE(0xbeef) would be 0xbe and LOBYTE(0xbeef) would be 0xef.