"The Last Question" is a science fiction short story by Isaac Asimov, published in 1956. It is about a question that is presented to a series of supercomputers over a long period of time. The story begins in 2061, with the activation of the new global supercomputer, Multivac. A pair of technicians, drunk from celebrating, discuss the theoretical future of humanity and the ultimate heat-death of the universe due to entropy. On a $5 bet, one of the technicians poses the question to Multivac: "How can the net amount of entropy of the universe be massively decreased?" Multivac responds with "INSUFFICIENT DATA FOR MEANINGFUL ANSWER".
The story skips ahead to several successive time periods in the far future, each with humanity having made tremendous advancements under the guidance of a supercomputer descended from the original Multivac (first Microvac/Planetary AC, then Galactic AC, then Universal AC, then Cosmic AC). In each time period, the question is put forth again of whether there is a way to reverse entropy, with each AC responding "THERE IS AS YET INSUFFICIENT DATA FOR A MEANINGFUL ANSWER".
Mankind eventually merges with AC, and the universe comes to an end. AC continues to exist in hyperspace, pondering the question that had first been asked ten trillion years earlier. AC spends an eternity calculating and correlating all data, until it realizes the answer to the last question. Although there is no longer anyone to give the answer to, AC is unconcerned, as the answer itself would solve that problem.
And AC said, "LET THERE BE LIGHT!" And there was light.