Problem-heuristic fit refers to how well a given problem solving strategy fits a particular problem. On the good side, this ranges from heuristics specifically designed for a problem domain to novel ways of applying heuristics to unexpected domains. Poor problem-heuristic fit is the notion communicated by the aphorism "When all you have is a hammer, every problem looks like a nail." Also related to Searching Under the Streetlamp and Bikeshedding. In programming, analysis of problem-heuristic fit is related to Big-O notation.