Independent Variable is a factor or phenomenon that causes or influences another associated factor or phenomenon known as dependent variable.
For Example : Income is an Independent Variable because it causes and influences another variable Consumption.
In a mathematical equation or model, the independent variable is the variable whose value is given.
In an experiment, it is the controlled condition whose effect on the behavior of a dependent variable is studied.
Independent Variable is also known as Controlled Variable, explanatory variable or predictor variable.