WRT the name, Material design is (very loosely) "Skeuomorphism in behavior, not in look". The idea is that things should act like their physical counterparts w

WRT the name, Material design is (very loosely) "Skeuomorphism in behavior, not in look". The idea is that things should act like their physical counterparts where it makes sense. So when you slide a drawer in from the left, it should cast a shadow on something below it, it should slide over-top of things. Things should always "come from" somewhere, instead of just fading in and out. They should have a "home", and that home should be consistent (EX: the drawer "lives" on the left of the screen, new items in a list should populate by zooming up from the bottom, etc...). That doesn't mean you can't violate the "laws of physics" by having stuff change shape and size, but the animations and effects should convey a sense that the dialog box or element you are interacting with is a "physical" thing. Opening a note in a ToDo app should zoom in from it's position in the list to the full screen, saving it should send it back to it's original location. 2 items at the same "elevation" on the screen should never slide over one another, they should either clearly go over or under one another. Deleting notes should send them offscreen somewhere, not just blink them out of existence. Buttons should ripple with ink from where you pressed them to convey that the click/touch was received. Action elements should stand out from the page like physical buttons with a shape and shadow and consistent positioning.