PVA's full chemical name is Polyvinyl Acetate. It's a very strong glue and non-toxic at that. PVA glue is also known as white glue or German glue. Unless you're playing with Superglue, most of the stuff you pull off of the shelves is composed of PVA and water. More concentrated mixtures are found in hobby stores and such, although some hardware stores stock it as wood glue. The best method for sticking is to liberally coat both materials, wait until they get sticky rather than runny, and then jam them together and keep them that way. Doesn't really work all too well for nonporous stuff like metal. Hobbyists find good PVA glue more useful than Superglue, because it's a ton cheaper and thus can be used over wide areas. Also, there's the notorious "clog" that Superglue has-- leave the tiny thing uncapped and unused for about fifteen seconds and you're in trouble. Let me clarify this point:
PERSON: Uh oh... the Superglue's uncapped. Wonder if it's dried too much.
(Person pokes at tube with index finger and gets tube stuck to finger. They then pick up the tube and get the nozzle stuck to their thumb. After that, they pry at their finger and thumb with their other hand and promptly get two more fingers and the other thumb stuck on the tube.)
At this point, "person" will usually spend five minutes dislodging their fingers only to discover that they need a toothpick because it just dried out again. By comparison, white glue just gets your fingers gooey. Also, picking dried glue off of the top has to be one of the most entertaining things in the world. At least if you've got the diluted stuff.