What is the point of having a control group in a Psychological experiment?

A control group allows us to have a base recording that we can compare our experimental group to. A control group and an experimental group are treated in the same way except for the variable that we are manipulating (independent variable). The experimental group is exposed to it, while the control group isn’t. That way, if we do find a difference between the two groups at the end of the study, we can feel confident it is because of our manipulation.