**Hypothesis Test: **A Hypothesis Test is a statistical method used in A/B testing where you test the validity of a claim or idea about a population parameter. In the context of A/B testing, it's a way to prove or disprove the assumption that a particular change (like a new webpage design or marketing strategy) will increase conversions or other key metrics. The objective of a hypothesis test is to determine which outcome— the original version (A) or the new version (B)— is more effective.