Engaging in sexually stimulating caressing or touching of the partner’s genital areas. Inside marriage, petting can be termed foreplay where both partners give and receive caressing to their bodies, often culminating in intercourse.
Outside marriage this is playing with fire
courtship, safeguards and boundaries should be established as to what is to be permitted, and in love hold each other accountable not to cross the line. This proves you truly care about the other person and desire to please God. Maintaining pure thoughts and self-control are both essential character qualities that need to be exercised, so sexual desires are not aroused. "Now flee from youthful lusts, and pursue righteousness, faith, love and peace, with those who call on the Lord from a pure heart" (2 Tim 2:22). Keep the time of sexual discovery and intimacy for when you are married.
See also: boundaries, caress, dating, purity, self-control, sexual sins, thinking/thoughts.