Another use for the Option key that I didn't see in the article: if you hold it down and click to another application (or on the desktop), all of the current ap

Another use for the Option key that I didn't see in the article: if you hold it down and click to another application (or on the desktop), all of the current application's windows will be hidden. It's the same effect as the menu item [Application] > Hide [Application] (⌘H).