Theory of Computation

What is a decision problem?
A decision problem is a question that has two basic outputs: yes or no. An
example of a decision problem would be “is the sky blue?” or “is 1 + 1 equal to
2?”
A decision problem is always associated with a decision procedure, which is a finite set of
steps to solve the problem and generate a decision. (Wikipedia)
 What does it mean for a decision problem to be decidable?
A problem is
decidable if there is a way to construct an algorithm that answers the problem
correctly. (Wikipedia)
 What is the class P? What is the class NP?
The class P consists of problems that are solvable in bigO polynomial
time, aka in time O(n^k) in their worst case. On the other hand, NPClass consists
of problems that are verifiable in bigO polynomial time, which means it is
easy to check if the answer is correct without the need of additional
information. (Tutorials Point)
 What is the intuitive meaning of the “P versus NP” question?
In general, P includes
easy problems in computation, and NP includes very difficult questions. The
intuition behind the P versus NP statement is that P = NP implies that the hard
problems in in NP should actually have relatively easy solutions. (Tutorial
Point)

If you resolve the P versus NP question, how
much richer will you be?
The reward for solving the problem is 1,000,000 granted by Clay Mathematics
Institute. (The Conversation)
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