Time Out For a Quick Game
Once upon a time, when you said the words "role playing game" you did not mean a game played on a computer. They were played with pencil and paper and a series of distinctive dice, based on the Platonic solids: a 4-sided die on a tetrahedron, 6-sided on a cube, 8-sided on an octahedron, 12-sided on a dodecahedron, and 20-sided on an icosahedron. As gaming moved on, it was common to add a pair of 10-sided dice, on petagonal bipyramids, which aren't platonic solids, but do, conveniently, have 10 sides. These were used singly to roll values between 1 and 10, and in pairs to roll percentages, or percentile dice.