A hypothesis is a concept or idea that is tested through research and experiments. In other words, it is a tentative prediction about the outcome of a study that can be tested by research. It is developed before the data is collected based on the existing body of knowledge in a particular area of study. Data is then collected, analyzed, and used to support or negate the hypothesis, arriving at a definite conclusion at the end of the research.

Thus basically, you make a prediction about the outcome at the start of the study and conduct experiments to test whether this prediction is true and to what extent. 

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