Piaget's theory of cognitive development outlines 4 stages of development: the sensorimotor stage from birth to age 2 where infants make sense of the world through senses and motor skills, the preoperational stage from ages 2 to 7 where language develops and imagination is used, the concrete operational stage from ages 7 to 11 where logical thinking of concrete concepts emerges, and the formal operational stage from ages 12 to adulthood where abstract thinking and problem solving develop.