Foreplay refers to a wide variety of erotic stimulation that precedes "real" sex or sexual intercourse. However, behaviors that commonly are labeled as foreplay are pleasurable sexual activities in their own right and need not be thought of only as preliminary to other activities.

In the era of AIDS, there has been growing emphasis on sexual contact that does not lead to intercourse. Some forms of this behavior, in which orgasm occurs without inserting the penis into the vagina or any other body cavity, have been referred to as outercourse.

As part of a broader sexual interaction, foreplay is considered to be an essential component that stimulates and prepares the body and the mind/emotions to move through the phases of the sexual response cycle in preparation for orgasm.

Foreplay — The Erogenous Zones
Touch is a key element of foreplay because the surface of the body is covered with many receptor cells (nerve endings) that transmit pleasurable sensations to the brain. Some parts of the body, particularly the clitoris, penis, nipples, fingertips, palms, lips, tongues, and soles of the feet have more densely packed nerve endings.

These sites are sometimes called the erogenous zones, although, in fact, the entire surface of the skin has been referred to as the body's largest sex organ because all forms of pleasure during foreplay are transmitted through the skin. Consequently, caresses, hugging, holding hands, and related acts of physical intimacy, in addition to expressing key cultural meanings about caring, safety, and arousal, are important acts of foreplay.

Foreplay — Light Touching
Many people also find light touching or tickling of the surface of the skin to be especially stimulating. Back rubs and massages(with or without massage oil or other artificial lubrication) are considered to be very erotic by some. Others prefer more intensive hand to body caressing and exploration of the erogenous zones, commonly referred to as petting.