Endianness

Endianness describes the order in which bytes are stored in memory for multi-byte values. The options are generally described as big-endian or little-endian. A big-endian system stores the most significant byte at the smallest memory address and the least significant byte at the largest. A little-endian system stores the least significant byte at the smallest memory address and the most significant byte at the largest.

Example

To store the 32-bit integer 0x0A0B0C0D, it is broken down into four bytes:

  • 0x0A
  • 0x0B
  • 0x0C
  • 0x0D

The endianness of the computer system defines in what order these bytes are stored in memory. The following examples show it stored at memory address 0xFFF0 for both big- and little-endian systems:

Big-endian

Address Value
0xFFF0 0x0A
0xFFF1 0x0B
0xFFF2 0x0C
0xFFF3 0x0D

Little-endian

Address Value
0xFFF0 0x0D
0xFFF1 0x0C
0xFFF2 0x0B
0xFFF3 0x0A

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