> in the order they'd be input into the machine That is the usual why for little endian. Same reason why little endian byte ordering is used on the 8008 and s

> in the order they'd be input into the machine That is the usual why for little endian. Same reason why little endian byte ordering is used on the 8008 and successors. The processor needs the lower byte first, to calculate the carry over to the high byte. Bit serial machines (like the Mark 1 and most other early computers) operate in a similar manner, just one bit at a time, from least to most significant digit.