Close Windows When Quitting Apps in Mac OS X Selectively or Always
Mac OS X defaults to automatically re-opening windows when an application is quit and relaunched later. This feature is borrowed from iOS and it’s incredibly useful, and once you become dependent on it you’ll find that it can really increase your productivity by allowing you to get back to work quickly. This is especially true when you need to quit out of an app or ten to free up resources for another task, or just to help maintain focus and stay productive when too much is going on.