  After more than a century since its birth, Quantum Theory still eludes our
understanding. If asked to describe it, we have to resort to abstract and ad
hoc principles about complex Hilbert spaces. How is it possible that a
fundamental physical theory cannot be described using the ordinary language of
Physics? Here we offer a contribution to the problem from the angle of Quantum
Information, providing a short non-technical presentation of a recent
derivation of Quantum Theory from information-theoretic principles. The broad
picture emerging from the principles is that Quantum Theory is the only
standard theory of information compatible with the purity and reversibility of
physical processes.
