Theory of Computation

A decision problem is a problem which can be answered with a ‘yes’ or ‘no’. Determining answer to the ‘Do you want to go to the park?’ question is a decision problem as well.
If there is a problem for which we cannot approximate the exact time/complexity/iterations the problem will be solved. For example, it is impossible to answer with the exact time you can become a billionaire, although it is still possible
Class P contains all the problems that can be solved within polynomial complexity, while NP class contains those problems which we can solve with verification of a certain answer in polynomial time. For NP, we may come to the right answer after verifying all the previous, not right, ones.
The problems for which we can check in polynomial time if an answer to them is right or not, in case P=NP, are also fully solvable in polynomial time.
Depends on my ethical part of personality and the way I have resolved the problem. If my proof to the solution is constructive, then I have a way to hack any bank account in the world (if I decide to do so). However, if I only proof that P is equal to NP or not, then I get not much from that, except for the prize of $1,000,000 promised for the problem.