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a dynamic move ordering method based on the number of cutoffs caused by a given move irrespectively from the position in which the move has been made. The Heuristic was invented by [[Jonathan Schaeffer]] in 1983 <ref>[[Jonathan Schaeffer]] ('''1983'''). ''The History Heuristic''. [[ICGA Journal#6_3|ICCA Journal, Vol. 6, No. 3]]</ref> and works as follows: on a [[Beta-Cutoff|cutoff]] we increment a counter in a special table, addressed either by <span style="background-color: #e0e0e0;">[from][to]</span> (the [[Butterfly Boards]]) or by <span style="background-color: #e0e0e0;">[piece][to]</span> <ref>[[Jos Uiterwijk]] ('''1992'''). ''Memory Efficiency in some Heuristics''. [[ICGA Journal#15_2|ICCA Journal, Vol. 15, No. 2]]</ref> . The added value is typically <span style="background-color: #e0e0e0;">depth * depth</span> or <span style="background-color: #e0e0e0;">2 ^ depth</span>, based on the assumption that otherwise moves from the plies near the leaves would have to much impact on the result. Values retrieved from that table are used to order non-capturing moves. This simple heuristics performs usually better than domain-dependent heuristics, though it may be combined with them. For example, in [[Rebel]] only a few non-captures are ordered by history heuristics, then a piece-square approach is used <ref>[httphttps://web.archive.org/web/20070927195511/members.home.nl/matador/chess840.htm#MOVE%20ORDERING Move Ordering in Rebel] by [[Ed Schroder|Ed Schröder]], also available as [httphttps://members.homesilo.nltips/matadordownload/Inside%20Rebel.pdf how-rebel-plays-chess-1 pdf]</ref> . In the literature, history heuristic is often presented as depth-independent generalization of the [[Killer Heuristic|killer moves]]. It is also said to reflect long-term plans in a position.

* [https://web.archive.org/web/20180713063523/http://members.home.nl/matador/hr.htm History Reductions] from [[Ed Schroder|Ed Schröder's]] [http://members.home.nl/matador/stuff.htm Programmer Corner]([https://en.wikipedia.org/wiki/Wayback_Machine Wayback Machine], July 30, 2007)