Highbyte

Highbyte is a term used in computing to denote the most significant byte of a multi-byte integer or word. In a 16-bit value, the high byte contains bits 15 through 8; in a 32-bit value, it is bits 31 through 24, and so on. The high byte is sometimes called the high-order byte or the most significant byte (MSB byte).

Endianness describes how bytes are arranged in memory. In big-endian systems, the high byte is stored at the lowest memory address; in little-endian systems, the high byte is located later in memory, even though it holds the same value. This distinction matters for data interpretation, transmission, and file formats that assume a particular byte order.

Applications of the high byte appear in data encoding, network protocols, and file formats that treat multi-byte fields as sequences of bytes from most to least significant. The high byte often plays a key role in value extraction, serialization, and network byte order conventions, where data is standardized to a common endianness for transmission.

Common methods for handling the high byte include shifting and masking to isolate it or to assemble a complete value from its bytes. For example, a 16-bit value’s high byte can be obtained as (value >> 8) & 0xFF, while for a 32-bit value the high byte is (value >> 24) & 0xFF. These operations underpin tasks in low-level programming, data parsing, and systems interoperability.

Related concepts include the most significant byte, the least significant byte, endianness, big-endian, and little-endian. Note that some contexts use “highbyte” as a variable name or product name; for a specific entity bearing that name, a distinct article would be appropriate.