This is a primitive question but needed to be answered as a first step in the evolution of experimentation. Over time, the questions have become more sophisticate e.g., Can a change in an existing process produce a measurable effect on the product or environment? Can the measurable characteristics of a process be used to predict the measurable characteristics of the product or environment, within a particular context? Can we control for product effects, based upon goals, given a particular set of context variables?