There is a "real and important" difference between engineering and physics as similar to any science field has to do with technology. Physics is an exploratory science that seeks knowledge of principles while engineering uses knowledge for practical applications of principles. The former equates an understanding into a mathematical principle while the latter measures variables involved and creates technology. For technology, physics is an auxiliary and in a way technology is considered as applied physics. Though physics and engineering are interrelated, it does not mean that a physicist is trained to do an engineer's job. A physicist would typically require additional and relevant training. Physicists and engineers engage in different lines of work. But PhD physicists who specialize in sectors of engineering physics and applied physics are titled as Technology officer, R&D Engineers and System Engineers.