ABSTRACT
It is important to distinguish a theory from a model. A theory is a plausible general principle or body of principles o“ered to explain a phenomenon or a prediction based on previous observations or experiments. e 2005 edition of e American Heritage Dictionary dešnes a model in scientišc applications as “a systematic description of an object or phenomenon that shares important characteristics with the object or phenomenon.” at is, a model is a simplišed system that illustrates or exhibits the same behavior as the more complex system. eories are not testable whereas models enable testable hypotheses. While no single model can be expected to represent all aspects of a complex motor behavior such as handwriting, some models are better capable of generating testable hypotheses than others.