The term regression was 1st used by the british biomethician sir Francis Galton. While studying the relation between average height of their children ,Galton found that the off springs of abnormally tall or short parents tend to regress or step back to the average population height . in the course of time the meaning of the word “ Regreassion “ become wider and now it stands to measure the average relationship between different variables. If there are only 2 variable under study then one is taken as independent and another is taken as dependent variable and regression analysis explain how on the average the values of the dependent variable change with a change in the values of the independent variable.