What are controls in an experiment?
The controls in an experiment are a variable that is left unchanged to see what the effects of the changed group are in relation to the control. Its kind of hard to explain. For instance, if one is testing out a new medication, one can issue the new medication to one group of people, another group of people will receive the old medication, another group of people will receive a placebo, and the fourth group (control) would receive no medication.
