In my opinion, it is very important to understand clearly when to use Pearson, Spearman, or Chi-square tests. These tests help us know if two variables are connected or related. Pearson is used when both variables are numbers. The data should be normal and show a straight-line pattern. It tells us how strong the relationship is between them. Spearman is used when the data is not normal. It also works when the data is in order or rank, like small, medium, and large. It tells us if the order of the numbers is related. Chi-square is used when the data is in groups, like colors, gender, or types of food. It helps us see if the groups are related. Before choosing a test, we need to look at the type of data and if the data is normal. If we do not choose the right test, the results can be wrong or misleading.