Hi, I've been on the other PF forums for some months, where QM is often mentioned and I assumed I had some basic understanding of it, but I thought I would come here to clarify. I read http://en.wikipedia.org/wiki/Quantum_mechanics" [Broken] on it and I'm still unsure if I have it right or even complete. From what I have read, using my own words, QM is about discrete particles and how their internal energy is affected/used/conserved, and/or what that energy is at any instance in time, (allowing for the uncertainty principle). Following on from this, I read that Planck considers waves to be made up of small packets of this quanta. The way I visualized this is like a fog, that when examined closely is made up of tiny droplets of water, each droplet being a packet of many water molecules. Is this what is meant by quanta in QM, that each packet in a wave is a discrete packet of particles, spatially separate from the next packet? And by wave, I imagine that to mean like a beam of light or heat from the sun.