Heuristic: n. a mental shortcut that helps make problem solving and decision making more efficient
As decision makers, we possess a variety of heuristics that are used for different tasks. For example, the recognition heuristic (RH) helps us compare two choices when we recognize one object in a decision pair, but not the other. In Goldstein and Gigerenzer (2002), participants used the RH to decide which out of two cities had the larger population - San Diego or San Antonio. Two-thirds of the American participants correctly answered San Diego, but all of the German participants gave this correct answer. Because they had never heard of San Antonio and only recognized San Diego, the RH worked to their advantage.
Other examples of heuristics that we frequently use are the availability heuristic, Take The Best (TTB) heuristic and the representativeness heuristic.
Reimer, T., Rieskamp, J. (2007). Fast and Frugal Heuristics. Retrieved January 20, 2013 from http://web.ics.purdue.edu/~treimer/Reimer_Rieskamp_2007.pdf.