An element is a very simple base trick or movement. For example, in terms of front style play, Brain Twister is an element for combos. We use Brain Twister and its variations a bunch in front style, even though the trick itself is a very basic trick. The reason is because it looks good when you can chain a bunch of different elements, no matter how simple, together in a smooth, practiced fashion.
In terms of innovative whips, slacks, lacerations, hops, isos, etc., they are made up by the players.