Apparantly Americans believe the term 'snog' or 'snogging' to be the British term to 'Make out', where its not just a passionate kiss, but includes anything and everything, including having sex.
They even have a scale:
1 Sticky Eyes
2 Holding Hands
3 Arm Around
4 Goodnight Kiss
5 Kiss lasting over 3 mins. w/out a breath
6 Open Mouth Kissing
8 Neck Nuzzling
9 Upper body fondling: outdoors
10 Upper body fondling: indoors (in bed)
11 Below Waist Activity (b.w.a.)
12 The Full Monty!!
13. Chomp!!!! (for Raptor)