Quantum physics is a branch of science that deals with discrete, indivisible units of energy called quanta as described by the Quantum Theory. There are five main ideas represented in Quantum Theory: 1. Energy is not continuous, but comes in small but discrete units. 2. The elementary particles behave both like particles and like waves. 3. The movement of these particles is inherently random. 4. It is physically impossible to know both the position and the momentum of a particle at the same time. The more precisely one is known, the less precise the measurement of the other is. 5. The atomic world is nothing like the world we live in. While at a glance this may seem like just another strange theory, it contains many clues as to the fundamental nature of the universe and is more important then even relativity in the grand scheme of things (if any one thing at that level could be said to be more important then anything else). Furthermore, it describes the nature of the universe as being much different then the world we see. As Niels Bohr said, "Anyone who is not shocked by quantum theory has not understood it." Quantum mechanics is the study of mechanical systems whose dimensions are close to the atomic scale, such as molecules, atoms, electrons, protons and other subatomic particles. Quantum mechanics is a fundamental branch of physics with wide applications. Quantum theory generalizes classical mechanics to provide accurate descriptions for many previously unexplained phenomena such as black body radiation and stable electron orbits. The effects of quantum mechanics become evident at the atomic and subatomic level, and they are typically not observable on macroscopic scales. Superfluidity is one of the known exceptions to this rule. In conclusion? Basically, I think that Quantum Physics is the field. It's what Quantum Physicists do. Quantum Mechanics is a part of the field. It's what Quantum Physicists use. QM usually refers to Wave Mechanics (Schrodinger et al) but can refer to Particle Mechanics (Einstein/Dirac) as well. QM is supposed to be distinct, as pointed out, from the relativistic theories like QED (Quantum Electro-Dynamics - Feynman et al). References: http://en.wikipedia.org/wiki/Introduction_to_quantum_mechanics http://en.wikipedia.org/wiki/Physics http://en.wikipedia.org/wiki/Experimental_physics

Quantum Mechanics is more or less theory - I guess, wheras quantum physics tries to make it visible through experiments.

QM attempts to create a mechanical system of interactions between subatomic particles...in the classical sense this is similar to a system of billiard balls colliding with one another. QP is everything associated with the physical phenomena of the small.