Decidability

Decidability refers to whether a problem can be definitively solved with a clear procedure or algorithm within finite time. In computational terms, a problem is decidable if there exists a systematic way to always determine the correct answer—“yes” or “no”—for any given input. Conversely, an undecidable problem is one for which no such universal method exists, meaning computers cannot consistently provide an answer in all cases. This concept helps differentiate problems that are solvable through algorithms from those that are inherently unsolvable with current computational methods.