In human sexual behavior, foreplay is a set of emotionally and physically intimate acts between two or more people meant to create sexual arousal and desire for sexual activity. Either or any of the sexual partners may indicate sexual interest to initiate foreplay, and the initiator may not be the active partner during the sexual activity. Foreplay stimulates both partners' sexuality, lowers inhibitions and increases emotional intimacy between partners, and implies a certain level of confidence and trust between the partners. In animal sexual behavior, the loose equivalent is sometimes termed 'precoital activity'.
Sexual desire is an aspect of a person's sexuality, which varies from one person to another. A person who desires sexual activity with another person can provoke sexual arousal in the person. Depending on the type and intensity of the relationship between the two people, the stimuli may involve indicating to the person in some subtle and romantic way that he or she has that desire or by provoking other erotic stimuli. There are many potential stimuli, both physical, and/or mental which can cause a person to become sexually aroused, and which stimuli are invoked will depend on circumstances at a particular time.
On the other hand, there are other things which act as turn-offs, depending on the person's preferences. The response to an indication of sexual interest may be inhibited by issues of sexual morality.
Foreplay can begin with one person indicating in some manner to another person a desire to engage in sexual activity with that other person. Any act that creates and enhances sexual desire, interest, stimulation or arousal in a sexual partner may constitute foreplay. An indication of sexual desire can be through physical intimacy, such as kissing, touching, embracing or nibbling the partner. Mental engagement can also create sexual interest, such as flirting, talking, whispering or teasing. It may, for example, be a non-physical gesture that indicates sexual availability. Sexual interest can be indicated and created by nudity, such as by one partner stripping, or by wearing sexually suggestive clothing, or by creating a romantic, intimate, or overtly sexual atmosphere. The manual or oral touching of an erogenous zone may indicate sexual interest, as does an intimate kiss on the mouth, breasts, stomach, , back and inner thighs or other areas of the body. A passionate or French kiss commonly indicates sexual interest, as does any removal of a partner's clothing.