Quantum Physics (also known as Modern Physics or Quantum Mechanics) is the branch of modern physics concerned with quantum theory. In simple terms, quantum theory is the science of extremely small things: atoms and subatomic particles. According to Quantum Theory, all matter (even an electron) and energy (such as light and heat) can behave like both a particle and a wave, at the same time. Although much of quantum theory is yet to be understood, some of it has been proven through experimentation and mathematical predictions that have turned out to be stunningly accurate. Quantum physics has come a long way, and we have been rewarded by a number of practical applications in recent years, from the creation of actual quantum computers to the development of RAIN.