2-samples t-tests (both equal and unequal variances) are parametric tests, which assumes that the data is normally distributed. What happens if the data is not normally distributed? We will have to use the non-parametric equivalent of 2-samples t-test, which is Mann Whitney U Test.

In this video, we will look at Mann Whitney U Test, also known as Mann Whitney Wilcoxon Test or Wilcoxon Rank-Sum Test.