It’s easy to find yourself with a dozen open apps and one or more windows for each app open on your desktop. Luckily, there are some efficient ways to see and navigate the windows you have open. When you want to focus, you can expand one app to fill the whole screen or choose two apps to share the screen. When you need to find a window that’s buried, use Mission Control to show all your open windows in a single layer. You can even create multiple desktops (called spaces) to view only specific windows, and then move between the spaces.
That horizontal traffic light. The red, yellow, and green buttons in the top-left corner of every window aren’t just for show. Click the red button to close an app window. For some apps, this quits the app and closes all open windows for the app. For others, it closes the current window but leaves the app open. The yellow button closes the window temporarily and puts it in the right side of the Dock. When you want to reopen it, click it in the Dock to expand it. And the green button is a quick way to change your windows to full screen and Split View, and more.