Unless you expect to publish for an older version of Flash, you will likely select ActionScript 3.0 in order to create a new document.
Once you have a document open, several items on the screen will change. First, the Stage is visible. It is the white box in the middle of the screen. Anything that is placed in the stage area will be visible in the final output. Animations might start off stage and fly in before leaving off the other side of the Stage. To see the content on the Stage better, you might want to zoom in or out.
Note: Even objects off stage can sometimes become visible to users.
The Timeline is the area to organize the layers of items, and when they happen during the animation. The Timeline will be covered in detail later in the lessons.