Here is a full glossary from a good website - askphil ....
http://www.askphil.org/b25.htmYou might want to start by picking up a basic book about stamp collecting from the library .. look for something relatively new, because even though it is an old hobby, some concepts and trends have certainly changed over the years.
Eventually, you will be looking at a good catalogue as a reference. The Scott guides and catalogs are the standards in the U.S.