In research, variables of different nature are used. Two major variables used in such case is Independent and Dependent variables.

A variable (often denoted by x ) whose variation does not depend on that of another is called as Independent variables. Other names for Independent variables are exogenous variable, predictor variable, regressor, controlled variable, manipulated variable, explanatory variable, exposure variable (in reliability theory), risk factor (in medical statistics), feature (in machine learning and pattern recognition) or an "input variable."

A variable (often denoted by y ) whose value depends on that of another is known as Dependent variables. Other names for Dependent variables are Endogenous variable (similar not exactly the same as dependent variables), response variable, regressand, predicted variable, measured variable, explained variable, experimental variable, responding variable, outcome variable and output variable.