Elements

http://www.youtube.com/watch?v=ssaUusY6hWM&feature=related
you can take a look at this.. quite joker lah.
Recap.. Elements are particles made up of only one type of atom.
One type of atom as in single element. Examples are.. H2 O2 so yeah.. when two atom same type of element chemically joined together it is still an element BECAUSE it's only made up of one type of atom. Such particles are called molecules. That means yes all compounds are molecules.
The common ones are
Oxygen(O)
Hydrogen(H)
Chlorine(Cl)
Sodium(Na)
Copper(Cu)
Iron(Fe)
Silver(Ag)
Gold(Au)
Argon(Ar)
Carbon(C)
Potassium(K)
Maybe enough for examples. Those elements are based on my knowledge because I didn't really go and memorize all this. Actually don't have to memorize just need to familaries it.
As you can see most of their symbols take the first letter either from the name or it's latin name.