A conceptual framework within which observations are explained and new ones predicted. In its construction, a theory draws upon any existing principles and laws in a particular area of science, and then serves to generate hypotheses to test the explanations and predictions it offers, possibly with the aid of models. A hypothesis that survives rigorous testing may become a theory itself.
See Explanation, Hypothesis, Hypothetico-deductive method, Law, Method, Model, Paradigm, Prediction and explanation, Principle, Procedure, Technique