Motivation is defined as the process that initiates, guides, and maintains goal-oriented behaviors. Motivation is what causes us to act, whether it is getting a glass of water to reduce thirst or reading a book to gain knowledge.It involves the biological, emotional, social, and cognitive forces that activate behavior. In everyday usage, the term motivation is frequently used to describe why a person does something. For example, you might say that a student is so motivated to get into a clinical psychology program that she spends every night studying.

"The term motivation refers to factors that activate, direct, and sustain goal-directed behavior... Motives are the "whys" of behavior - the needs or wants that drive behavior and explain what we do. We don't actually observe a motive; rather, we infer that one exists based on the behavior we observe."

Psychologists have proposed a number of different theories of motivation, including drive theory, instinct theory, and humanistic theory.

Components of Motivation