Operant conditioning (also called instrumental conditioning) is a learning process through which the strength of a behavior is modified by reinforcement or punishment. It is also a procedure that is used to bring about such learning.

Although operant and classical conditioning both involve behaviors controlled by environmental stimuli, they differ in nature. In operant conditioning, stimuli present when a behavior is rewarded or punished come to control that behavior. For example, a child may learn to open a box to get the candy inside, or learn to avoid touching a hot stove; in operant terms, the box and the stove are "discriminative stimuli". Operant behavior is said to be "voluntary": for example, the child may face a choice between opening the box and petting a puppy.

In contrast, classical conditioning involves involuntary behavior based on the pairing of stimuli with biologically significant events. For example, sight of candy may cause a child to salivate, or the sound of a door slam may signal an angry parent, causing a child to tremble. Salivation and trembling are not operants; they are not reinforced by their consequences, and they are not voluntarily "chosen".

The study of animal learning in the 20th century was dominated by the analysis of these two sorts of learning,[1] and they are still at the core of behavior analysis.

From https://en.wikipedia.org/wiki/Operant_conditioning