what is control variable

A control variable, also known as a scientific constant, is an experimental element that is held constant and unchanged throughout the course of an investigation. Control variables are not of primary interest to the experimenter, but they are important because they could strongly influence experimental results if they were not held constant during the experiment. Control variables can be anything that is held constant or limited in a research study, and they are not of interest to the studys objectives, but are controlled because they could influence the outcomes. Variables may be controlled directly by holding them constant throughout a study, or they may be controlled indirectly through methods like randomization or statistical control. Control variables can help prevent research biases like omitted variable bias from affecting the results. In most science experiments, there are three variables: the independent variable, the dependent variable, and the control variable. The independent variable is the variable that is being changed or manipulated, while the dependent variable is the variable being measured. The control variable is an element that is kept the same throughout the experiment in order to assess the relationship between multiple variables.