Students Experimental method is the most precise, planed, systematic and controlled method. It uses a systematic procedure called as experimental design. The term experimental design has tow different meanings one is the experimental design which represents the six basic steps we have referred above Followed in an experiment. The second meaning of experimental design and selecting an appropriate statistical procedure. Experimental design provides important guidelines to the researcher to carryout his research study. Experimental design ensures adequate controls by avoiding irrelevant causes of variability. The layout of a design depends on the type of the problem the investigator wants to investigate. Students you should know that, no one design solves all the problems of a research study. A variety of experimental designs have been developed by researchers in recent years. These designs differ as these are dependent upon a) the nature of problem b) the situation c) the subjects and their availability. Let us study some of the experimental designs used while employing Experiment method. Following are the samples of experimental designs.