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an American engineer, [https://en.wikipedia.org/wiki/United_States_Chess_Federation USCF] chess master, chess journalist, columnist and instructor. He earned a B.Sc. in mathematics in 1971 and a M.Sc in engineering in 1983, both from the [https://en.wikipedia.org/wiki/Pennsylvania_State_University Pennsylvania State University] <ref>[https://en.wikipedia.org/wiki/Dan_Heisman Dan Heisman from Wikipedia]</ref>. As early member of the [[ICCA]], Dan Heisman volunteered at the [[Deep Blue]] versus [[Garry Kasparov]] matches in [[Kasparov versus Deep Blue 1996|1996]] and [[Kasparov versus Deep Blue 1997|1997]] <ref>[http://web.archive.org/web/20070204023455/http://www.chessville.com/editorials/Interviews/Heisman_Part_1.htm Chessville - Interviews - Dan Heisman - Part 1], February 2003 ([https://en.wikipedia.org/wiki/Wayback_Machine Wayback Machine])</ref>.

=ElementsThe Value of Reaching a Square= In his book ''Elements of Positional Evaluation'' Dan Heisman <ref>[[Dan Heisman]] ('''1990, 1999, 2010'''). ''[https://www.danheisman.com/elements-of-positional-evaluation.html Elements of Positional Evaluation]''. Russell Enterprises</ref>, Dan Heisman represents an attempt at mathematical abstraction applied to chess, introducing seven concepts as fundamental in analyzing a chess position: [[Mobility|mobility]], flexibility, vulnerability, [[Center Control|center control]], piece coordination, time and speed.