Byte Order 
Also known as Big-Endian.  Which means the most significant byte comes first in storage.  Sparc and Motorola 68k based chips are MSB ordered. 
(SDL defines this as SDL_BYTEORDER==SDL_BIG_ENDIAN)
Little-Endian(LSB) is stored in the opposite order, with the least significant byte first in memory.  Intel and AMD are two LSB machines. 
(SDL defines this as SDL_BYTEORDER==SDL_LIL_ENDIAN)
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