Big endian vs Little endian

8 bits is a byte.

4 bytes is a word.

Above figure shows a 32 bit processor register.

Byte order: Byte3 Byte2 Byte1 Byte0

Little Endian: lower order byte of a number is stored in memory at lower address, and the higher order byte is stored at higher address.

Big Endian: lower order byte of a number is stored in memory at higer address, and the higher order byte is stored at lower address.

Example:

1001 / 2 = 1

500 / 2 = 0

250 / 2 = 0

125 / 2 = 1

62 / 2 = 0

31 / 2 = 1

15 / 2 = 1

7 / 2 = 1

3 / 2 = 1

1 / 2 = 1

= 1111101001(binary)