0x1991

0x1991 is a hexadecimal numeral commonly used in computing. The prefix 0x indicates base-16 representation, so the digits 1, 9, 9, 1 form the value. In decimal, 0x1991 equals 6545. In binary, it is 0001 1001 1001 0001, with bits set at positions corresponding to the 1s. The value is treated as an unsigned integer in most languages.

In programming, 0x1991 is typically used as a constant. It may serve as a numeric value for initialization, as a bitmask, as an offset or address in memory, or as a hardware register selector on architectures that expose registers via hex offsets. Its meaning is entirely context-dependent and is determined by how the program interprets the value.

In software documentation, 0x-prefixed hex literals are a convention in languages such as C, C++, Java, JavaScript, Python, and many assembly languages. The same digits could also appear in configuration files or data formats where hexadecimal notation is allowed.

There is no widely recognized entity, standard, or concept specifically named "0x1991" beyond its role as a hex literal. It is primarily notable as an example of hexadecimal notation used in software development and digital systems.

See also: hexadecimal notation, 0x prefix, decimal, binary, memory addressing, bitmask.