Motivation is a reason or set or reasons for engaging in a particular behaviour, especially human behaviour as studied in psychology and neuropsychology. The reasons may include basic needs (e.g., food, water, shelter) or an object, goal, state of being, or ideal that is desirable, which may or may not be viewed as "positive", such as seeking a state of being in which pain is absent. The motivation for a behaviour may also be attributed to less-apparent reasons such as altruism or morality.