Regression Models and Least Square Methods

What is Regression?  

Having a strong correlation between the values of two variables means that we can determine a straight line such that the points in the scatterplot either lie on this line or significantly closer to the line. This line is called regression line and the equation represents this line is called regression equation.

We use regression method more often for prediction purpose in applied statistics. That is, using the data collected about a real life situation in the past we try to define a pattern for it and based on that pattern to examine and predict what would happen in the future.

Simple regression model utilizes an independent variable to predict the dependent variable or vice versa.