I don’t understand that what does this term “Regression” means?

Hi @SHVNG, welcome to the DLS community and thanks for your question. I am actually not exactly sure what which course or video your question relates to, but I assume your question is why the term is regression is called “regression” and not something else. There is actually some history behind it, and the term originally came from Francis Galton (see [Regression analysis - Wikipedia](Regression analysis - Wikipedia, or JMPer Cable Summer 98: Why is it called Regression? (jhsph.edu)) who did his version of data science analysis in the 19th century. He looked at the length of children and compared these to the length of the parents, and found that longer parents tend to have smaller children, and smaller parents tend to have taller children. Let aside the reason, but he termed it as the children are “regressing”, i.e. returning back, to a normal average. Hence the term regression was born, and has stuck around for any analysis estimating the relationship between a dependent variable and an independent variable.

Hope this clarifies.