Those are the two primary verbs of Defense Grid: The Awakening. You build towers on a gird and the aliens march from their entrance to an exit on the other side. In the middle is a source of energy that the aliens are trying to steal. Your towers kill the aliens. Sometimes you win by having energy at the end of the round.
One of the differences between this and other games within this genre is the ability to rewind time. As each round plays out, the game checkpoints you. Once that happens, you can rewind at any time to any checkpoint including the beginning of the round. This becomes incredibility important in later rounds when an early move can spell your doom many moves later.
I don’t like chess. The reason being that in order to win consistently, you must have an understanding of what you can do, what your opponent can do and future combination of the two. That is how you must play this game.
Each round must be planned out. In order to do that however, you have to have knowledge of which aliens will show up and when. To do this, you must play each round, discover the aliens that will appear and then rewind. One step forward, two steps back until you win.
If I can impart any knowledge to you about this game to you, it is this: be patient, learn from your mistakes and rewind often.