An independent variable is the variable that is changed in a scientific experiment.
Independent variables are the variables that the experimenter changes to test their dependent variable
Common Misspellings: independant variable
A scientist is testing the effect of light and dark on the behavior of moths by turning a light on and off. The independent variable is the amount of light and the moth's reaction is the dependent variable.
A change in the independent variable directly causes a change in the dependent variable.