Probability is a measure of the likelihood that an event will occur. It is quantified as a number between 0 and 1 (or 0% and 100%).

• 0% (Impossible): The event will definitely not happen.
• 50% (Uncertain): As likely to happen as not (like a fair coin toss).
• 100% (Certain): The event will definitely happen.

In prediction markets, prices reflect the "crowd's" aggregate estimate of this probability. If a share of "Yes" costs $0.60, the market is implying a 60% chance of the event occurring.