Dice are small cubes used in games, with each of the six sides showing a different number of dots, from one to six. When you roll dice, you never know which number will land face up, which makes them perfect for adding chance and surprise to board games, math problems, and decisions.

A single cube is called a die, though most people say “dice” whether they mean one or many. The dots on dice are arranged so that opposite sides always add up to seven: if you see a six on top, there's a one on the bottom.

People have been rolling dice for over 5,000 years. Ancient Egyptians played games with dice made from bones and stones. Today, dice appear in countless games, from Monopoly to Yahtzee to complex role-playing games that use dice with eight, twelve, or even twenty sides.

The phrase rolling the dice means taking a chance on something uncertain. If you haven't studied much but take a test anyway, you're rolling the dice with your grade. When something is dicey, it means risky or uncertain, like walking across a dicey old rope bridge. Dice turn any game into a contest where luck matters as much as skill, which is why they've fascinated players for thousands of years.