IEEE Floating Point Standard

The IEEE Floating Point Standard (IEEE 754)is an IEEE standard, used by many CPUs and FPUs?, which defines formats for representing [floating point numbers]?; representations of special values (e.g. infinity?, very small values, NaN?); five exceptions, when they occur, and what happens when they do occur; four rounding modes; and a set of floating-point operations that will work identically on any conforming system.

IEEE 754 specifies four formats for representing floating-point values: single-precision (32-bit), double-precision (64-bit), single-extended precision (80-bit) and double-extended precision (128-bit). Only 32-bit values are required by the standard, the others are optional though 64-bit is required by standard C.

Also known as IEEE Standard for Binary Floating-Point Arithmetic (ANSI/IEEE Std 754-1985) and IEC 559: "Binary floating-point arithmetic for microprocessor systems.

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