Croikey.
Let's take a number, say 16,777,215. In hex you would write this on paper as 00FFFFFF (extending to 32 bits for simplicity's sake).
Now for how this would appear in memory/registers in different endians...
Little endian (e.g. Intel CPUs):-
Code:
Offset 00 01 02 03
Data FF FF FF 00
Big endian (e.g. Motorola CPUs):-
Code:
Offset 00 01 02 03
Data 00 FF FF FF
In little endian, the least significant bits of a multi-byte integer are stored at the lowest address in memory.
In big endian, the most significant bits of a multi-byte integer are stored at the lowest address in memory.
Comprendez?