The independent, dependent variables and control are very important to an experiment because you cannot perform the experiment without all three of these things.

In an experiment you should conduct multiple trials in order to insure the experiment data is accurate. That way you can dispose of any outliers that you may see.

An independent variable is the variable that doesn't change. It is the one that is set no matter what happens.

The dependent variable is the variable that depends on the independent variable.

A control is the part of the experiment where you don't do anything to it. Like if you were growing bacteria, the control would be the plate that you keep shut that should not grow bacteria.