Heuristic Search in AI

The term Heuristic is used for algorithms which find solutions among all possible one. The Heuristic is a rule of thumb or judgement technique that leads to a solution but it provides no guarantee of success. Heuristic plays an important role in the searching process because they help to reduce the number of alternatives from an exponential number to a polynomial number.
So, we get a solution in a reasonable amount of time. The additional information about the properties of the specific domain which is built into the state and operator definitions is called Heuristic Information. A search using this Heuristic Information is called Heuristic Search or Informed Search.