Polyhedral dice derive their name from greek meaning "many-sided" -- as opposed to a standard six-sided die.
Polyhedral dice are available in many different variations. Some dice manufacturers sell them in a "set" of standard dice. A typical "set" of polyhedral dice would include:
- 4-sided (d4)
- 6-sided (d6)
- 8-sided (d8)
- 10-sided x2 (d10 & d100)
- 12-sided (d12)
- 20-sided (d20)
These dice are considered common and standard in gaming and used extensively in PnP roleplaying games. Typically a player would maintain a collection of dice and sometimes keep them in a dice bag.
In addition to the "standard" set of dice, dice with less common numeric ranges are sold.
Examples of these include: