As opposed to an algorithm (which contains a fully defined set of steps that will produce a specific outcome), heuristics are general recommendations or guides based on statistical evidence (e.g., "quit smoking to prolong your life," "males with college education are more likely to respond positively to this advertisement than ...") or theoretical reasoning (e.g., "the mechanism of the vitamin X synthesis as we understand it, implies that eating Y will reduce the deficit of X"). For more information about the concept of heuristic, see Kahneman, Slovic, & Tversky, 1982.

See also: Data Mining, Neural Networks, algorithm.