What is the difference between intrinsic and extrinsic motivation?

Intrinsic motivation comes from internal satisfaction, interest, or enjoyment in the activity itself, such as reading a book because you find it fascinating. Extrinsic motivation comes from external rewards or pressures, such as studying to earn a good grade or working for a paycheck. Research shows that adding extrinsic rewards to intrinsically motivated activities can actually decrease intrinsic motivation, a phenomenon called the overjustification effect. A child who draws for fun may draw less after being paid for it.