halving

Halving is the act of dividing a quantity into two equal parts, producing one-half of the original amount. The term is used in mathematics, science, finance, and everyday language to describe a reduction by 50 percent followed by subsequent reductions.

In arithmetic, halving is equivalent to multiplying by one-half. Repeated halving produces fractions with powers of two in the denominator. Halving is a common operation in scaling, dilution, and binary partitioning, where a set or interval is repeatedly split into two equal portions.

In computing, halving explains processes that reduce a search range or data size by approximately half, such as binary search algorithms and data structure optimizations. It is also used in scheduling or sampling tasks that require binary subdivision.

Bitcoin halving is a well-known use of the term in blockchain economics. The protocol reduces the block reward by 50 percent every 210,000 blocks, roughly every four years, from 50 BTC to 25 BTC, then to 12.5 BTC, 6.25 BTC, and so on. The event controls new supply and can influence miners' incentives and market dynamics, though it does not guarantee price movements.

Other contexts include population studies, where halving times or rates are used to describe rapid reductions, and physics, where half-life measures decay. While related, halving is typically discrete, whereas half-life describes continuous exponential decay.