Classical vs. operant

Classical conditioning (also called Pavlovian conditioning) generally concerns an involuntary, automatic response, such as blinking, salivating, or becoming anxious.

A stimulus (the US) that always produces the involuntary response (the UR) is paired with a neutral stimulus (the CS). After a number of pairings, the formerly neutral stimulus becomes capable of producing the response (now called the CR).

In contrast, operant conditioning (also called instrumental conditioning) generally concerns more voluntary behaviors, such as pressing a button, turning a key, or raising your hand.