Quantum mechanics (QM – also known as quantum physics, or quantum theory) is a branch of physics dealing with physical phenomena at microscopic scales, where the action is on the order of the Planck constant. Quantum mechanics departs from classical mechanics primarily at the quantum realm of atomic and subatomic length scales. QM provides a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter.

Not exactly what an average person would be able to get their head around. There is also an Introduction to quantum physics article, that is suppose to be less technical and easier to understand the basics of quantum physics.

Quantum mechanics is the body of scientific principles that explains the behavior of matter and its interactions with energy on the scale of atoms and atomic particles.Quantum mechanics ordains that the more closely one pins down one measure (such as the position of a particle), the less precise another measurement pertaining to the same particle (such as its momentum) must become.

Ok, a bit better, but most of the people would still not get the point of quantum mechanics (another name for quantum physics). I was pondering my head how the heck to explain such complex branch of science to a person that doesn't really care so much for the conventional science and its complicated lingo, but still wants to know what is going on and how does it reflect in their everyday life. So I stumbled upon an old YouTube animated video featuring Dr. Quantum - Superman and Einstein hybrid - explaining the quantum physics in a quite understandable and entertaining fashion.

Watch Dr. Quantum and I hope you will get the basic principals of quantum physics and know how to explain it to the next person in an understandable and intriguing way: