Big Endian and Little Endian

Big Endian and Little Endian are two different ways that computer systems store multi-byte values in memory. The terms refer to which byte (most significant or least significant) is stored first in a sequence of memory addresses.

Byte Order Storage Methods

• Little Endian − The least significant byte (low-order byte) is stored at the starting address (A), and the most significant byte (high-order byte) is stored at the next address (A + 1).

• Big Endian − The most significant byte (high-order byte) is stored at the starting address (A), and the least significant byte (low-order byte) is stored at the next address (A + 1).

The "high-order" byte contains the largest powers of 2 (2³¹, ..., 2²⁴ for a 32-bit value), while the "low-order" byte contains the smallest powers of 2 (2⁷, ..., 2⁰).

Example − 32-bit Value Storage

Consider the 32-bit hexadecimal value 0x12674592. This breaks down into four bytes: 12, 67, 45, 92.

Network Byte Order

To enable communication between machines with different byte ordering conventions, Internet protocols specify a canonical byte order called Network Byte Order. This standardizes data transmission over networks by using Big Endian format, ensuring consistent interpretation regardless of the host machine's native byte order.

Comparison

Conclusion

Big Endian and Little Endian represent fundamental differences in how multi-byte values are stored in computer memory. While Little Endian dominates modern processors, Big Endian remains important for network protocols and certain architectures. Understanding both formats is essential for system programming and cross-platform compatibility.