More often referred to as 'Making Out' or 'Rounding The Bases' (you know, getting to First Base, Second Base, Third Base...), and sometimes called 'Heavy Petting'. Petting is actually a term that covers a broad range of sexual behaviors, including giving/getting a hickey, deep kissing, and sexual touching of one's partner. The touching, caressing, massaging and kissing of another person's body can take place through the clothing or under the clothing, and 'heavy petting' usually involves removing some clothing and touching BELOW the waist.
Getting caught is often time of a negative consequence most teens experience at some time or another during adolescence - sometimes they get in trouble, sometimes its just embarrassing. On a more serious note, it only makes sense that since petting is progressively more sexual, that it carries greater risks and consequences. This is the first sexual behavior discussed so far that carries the risk of pregnancy or infection of a serious STD (Sexually Transmitted Disease), though this is not common. Still, it is a risk.
We've already talked about the risks of deep kissing, and there are no consequences to touching above the waist, or touching below the waist on the outside of clothing (some might argue that the risk to light petting is that it leads to heavy petting and that teens just cannot control themselves and will end up having intercourse - we disagree that teens have no control and believe that better and earlier, constant sex education will help teens remain in control of their hormones).
The greater risk is with 'heavy petting', petting below the waist and inside the pants and underwear, and then only if the same hand touches both person's genitals (meaning that when touching yourself and then your partner, you can transfer body fluids, including sperm, to your partner's genitals). This same risk is true when two people share the same sex toys in the same way. Even a tiny amount of fluid or sperm is enough to transfer a disease or get a girl pregnant (yes, sperm can live outside the body, though not for very long).