Null Hypothesis

A Hypothesis is a statement that could be true, which might then be tested.

The Null Hypothesis is a default position that states there is no effect, no difference, or no relationship between variables. It is the starting assumption in statistical testing, and the goal is often to gather evidence against it.

Example: Sam has a Hypothesis that "large dogs are better at catching tennis balls than small dogs".
The Null Hypothesis is "there is no difference in tennis ball-catching ability between large and small dogs"