The nervous systems of all animals support learning and memory. Without this ability, they could not survive. In humans, however, learning and memory have surpassed that of most, if not all other species. Learning and memory allow us dynamically interact to with our environment. By having the ability to change and tailor our behavior in response to the results this interaction, we are continually creating and re-creating both the world and ourselves. For over 100 years, psychologists have sought to explain learning and memory at many different levels. This quest has gone from simple notions of mental associations, to complex laws of operant and classical conditioning, to abstract and symbolic cognitive maps or neural networks, and finally, to the neural mechanisms in the brain itself. Learning and memory shape who we are and play important role in our behavior. In the units contained in this section, we invite you to sample what psychology has to offer in terms of explaining this central and critical aspect of ourselves.