What is an independent variable?

An independent variable is defined as a variable whose variation does not depend on that of another variable. In experiments or mathematical functions, the independent variable is the one that is manipulated or controlled to observe the changes it causes in the dependent variable. For example, in a study examining how temperature affects the germination of seeds, temperature would be the independent variable since it is changed to observe its effect on seed germination.

In contrast, a variable that depends on another variable is known as a dependent variable. A variable that can change its value suggests a broader definition that could apply to both independent and dependent variables without specifying the relationship. Finally, a constant value in an equation does not change and therefore cannot be considered an independent variable. Thus, identifying the independent variable as one that operates independently allows for clear understanding when examining cause-and-effect relationships in research or functions.