I want to know that is there any difference between NP- hard problems and Computationally hard problems or are these two terms used for the same thing? I have tried to search the solution but cannot get some reasonable answer. Can anybody please help?
As of current knowledge (until that P=NP question is answered): All NP-hard problems are computationally hard. But not all computationally hard problems are NP-hard (problems in P, with high exponents in the polynome, for example).
Note that "NP-hard" is a well defined class of problems in computer science. "Computationally hard" on the other hand isn't, as far as I know.