probability of obtaining test results at least as extreme as the results actually observed, under the assumption that the null hypothesis is correct

In statistics, a p-value is the probability that the null hypothesis (the idea that a theory being tested is false) gives for a specific experimental result to happen. p-value is also called probability value. If the p-value is low, the null hypothesis is unlikely, and the experiment has statistical significance as evidence for a different theory.

In many fields, an experiment must have a p-value of less than 0.05 for the experiment to be considered evidence of the alternative hypothesis. In short, a low p-value means a higher chance of the hypothesis being true.