What is the meaning of control and variable?

what i mean is the scientific meaningWhat is the meaning of control and variable?
In an experiment, the control is what you keep the same. If you were growing plants in various conditions, your control would be the one you used to compare with other plants.





Your variable is the thing you change, like the amount of light or water etc.What is the meaning of control and variable?
In an experiment, the control is the subject that is kept the same, to be compared with; the variable is then, obviously, changed to see how things will affect it (ie. double a drug dosage and see how it reduces someone's hay-fever or whatever)
In a scientific experiment the control is the group used to compare the results to - part of the trial, but not, for example, taking the drug being tested. This is to screen for the placebo effect - to 'calibrate' the results you might say. Generally, no one in the test knows if they are in the experimental group or control group.





The variable is the thing that is being changed in the experiment, for example a new cancer drug. More specifically there is the dependant and independant variables. the dependant is what you are changing, eg you administer the drug, and the dependant is the effect, eg the size of the tumour shrinking.