Public Displays of Affection, can be seen in the form of kissing, touching, groping, licking, nuzzling, cuddling, crossing hands into each other's opposite back pockets, etc. Usually spotted among new couples, frisky teenagers, and occasionally the "young at heart" (god help us).
Also, a handheld computer of sorts.
Jen and Craig's PDAs at the table were so intense that there was actually slobber on the green bean casserole.
Look at my new PDA!