Mul

Mul is short for multiply, the arithmetic operation of forming the product of two numbers or quantities. In standard arithmetic, multiplication is a binary operation that is associative and distributive over addition, and it is often denoted by symbols such as ×, ·, or *. The result of multiplying two numbers a and b is their product, written ab or a·b depending on notation.

In computing, mul is used both as the general concept of multiplication and as a specific name for an operation or instruction. Most high-level languages implement the multiplication operator with a symbol like *, but some libraries expose a function named mul (for example operator.mul in Python) to support functional programming patterns or to pass as a first-class function. In assembly language, ‘mul’ is an explicit instruction that multiplies operands; on x86 it often multiplies a register or memory operand by an implicit accumulator and stores the extended result in a pair of registers (for example EDX:EAX).

Performance and algorithms vary. Hardware multipliers compute small-integer products in constant time, while large-integer or arbitrary-precision multiplication may use algorithms such as Karatsuba, Toom-Cook, or Schönhage–Strassen to improve efficiency for large operands. Floating-point multiplication follows similar principles but includes rounding, normalization, and handling of special values like NaN and infinities in IEEE-754.

Etymology and usage: mul derives from Latin multiplicare, meaning to multiply. In mathematical notation and some programming contexts, mul is used as a textual alternative to the symbolic operator. See also multiply, product, times, operator.mul.