P vs. NP problem
The P vs. NP problem asks is it's possible to finding a solution to a problem as quickly it is to verify it. P and NP refers to the complexity classes of these problems.
P vs. NP is one of the seven Millennium Prize Problems.
The question Does every problem that can be quickly checked (NP) can also be quickly solved (P) ? If you can efficiently verify an answer, can you also efficiently find the answer in the first place?
The answer We don't know the answer yet. There is 2 possible scenarios.