This page deals with the concept of expectation as a thought or belief. For expectation in the context of probability theory and statistics, see expected value.

In the case of uncertainty, expectation is what is considered the most likely to happen. An expectation may or may not be realistic.

A less advantageous result gives rise to the emotion of disappointment. If something happens that is not at all expected it is a surprise. See also anticipation, hope.

An expectation about the behavior or performance of another person, expressed to that person, may have the nature of a strong request, or an order.