[d20] Retrieved July 10, 2014 from http://www.forbes.com/sites/davidewalt/2012/09/06/dice-chessex-gamescience-roll-randomn/
For tabletop gaming there are a variety of different die types that are used, many of which people outside the hobby don't know anything about. A dice collection is something that a gamer builds over time, often, it even becomes a source of pride. If you are just getting into tabletop gaming, dice will most likely be your first purchase.