endianness - Little Endian vs Big Endian?

Question

I'm having troubles wrapping my head on the two. I understand how to represent something in big endian.

For example -12 is 1111 1111 1111 0100

But why is the little endian representation 1111 0100 1111 1111 instead of 0100 1111 1111 1111?

Answer 1

Endianness is about byte address order. Little endian means the lower significant bytes get the lower addresses. Big endian means the other way around. So it's about the bytes (8-bit chunks) not nibbles (4-bit chunks). Most computers we use (there are a few exceptions) address bytes at the individual address level.

Taking the -12 example:

Little endian, in memory, would be:

000000: F4
000001: FF

Big endian, in memory, would be:

000000: FF
000001: F4