The white rectangular Stage area is where you can arrange objects as you want them to appear in your published file.
NOTE
You can open several documents at once and use document tabs, above the Stage, to navigate between them.
The Tools panel, next to the Stage, offers a variety of controls that let you create text and vector art. To learn more about tools in the Tools panel, select Help > Flash Tutorials > Creating Graphics: Draw in Flash and Help > Flash Tutorials > Text: Add Text to a Document.
Click the Pencil tool in the Tools panel. Click the Stroke color box in the Tools panel colors area, and select any color except white.
Drag around the Stage, without releasing the mouse, to draw a line. You've created Flash content. Your finished document will be much more impressive.
Click the Pencil tool in the Tools panel. Click the Stroke color box in the Tools panel colors area, and select any color except white. 
