Probability is about estimating or calculating how likely or 'probable' something is to happen. The chance of an event happening can be described in words, for example ‘certain’, ‘impossible ...

Probability or chance is how likely something is to happen. Probabilities are most commonly shown as fractions. The probability of getting 'tails' when you toss a coin is a 1 in 2 chance, or 1/2 ...