Parameters of GetFile()

[newbieg]

I'm just a bit confused as far as what the description in MSDN for GetFile() means.
http://msdn.microsoft.com/en-us/library/windows/desktop/aa364955%28v=vs.85%29.aspx

Quote from MSDN:
Return value

If the function succeeds, the return value is the low-order doubleword of the file size, and, if lpFileSizeHigh is non-NULL, the function puts the high-order doubleword of the file size into the variable pointed to by that parameter.

So I don't understand what the difference between the low-order and high-order doubleword is. Or better yet, what does high-order/low-order mean?

[modoran]

Don't waste your time using GetFileSize(), always use GetFileSizeEx().

If you insist on using GetFileSize() and the file is small enough, use it like this:
DWORD lFileSize=GetFileSize(hFile,NULL); //Small files... no need to check upper 32