Smart Work And Hard Work != (Smart And Hard)Work

 This is very common question. Any one can ask to you. What is the difference between smart work and hard work. You also ask question to any other persons. This is manly ask in interviews. Interviewers want to know about how to solve the problem.
   Taking a example of Labor and Engineer  both are working a common side. Engineer know the structure of building but Labor don't know. Engineer salary is much greater than labor salary because Engineer work is smart(He/She has degree of Engineering). In study periods he/she also hard and smart work. And other  hand Labor work and experience also matter for achieving above post of Labor. But Labor can't ahead to Engineer.