What is quantum information?

Quantum information breaks the rules of classical information in a way that could allow us to answer questions that a classical computer cannot. Imagine mailing a letter. You, as the person sending the letter, know what the letter says. But the situation is different for the person you're mailing the letter to. Until they read it, they generally won't know what it says. This is the way scientists think about information, at least in the classical sense. A computer stores information, sends and r...