an entire shape or object. * Use the Subselection tool to select a specific point or line in an object. * Use the Lasso tool to draw a freeform selection area. 4 A mask restricts the visible area of the layers beneath it. Only the area that is covered by the mask shows through.     3. Creating and Editing Symbols Movie clip, graphic, and button symbols keep your file size small while increasing your flexibility. A single symbol can be used countless times in a project, but the file's data only has to be included once. Lesson Overview In this lesson, you'll learn how to do the following: * Import Illustrator files * Create new symbols * Understand the difference between symbol types * Adjust transparency * Import assets into the library * Use library assets * Convert bitmap graphics to vectors * Reduce the file size of Flash documents * Apply web-safe colors This lesson will take about an hour to complete. If needed, remove the previous lesson folder from your hard drive, and copy the Lesson03 folder onto it.   Getting Started First, view the final project to see what you'll be creating as you learn to work with symbols. 1. Double-click the 03End.swf file in the Lesson03/03End folder to view the final project in Flash. Move the mouse over the buttons to see their rollover states. The project is a DVD interface, designed to help a viewer navigate among the options on a DVD. In this lesson, you'll use Illustrator graphic files, imported JPEG files, and symbols to create an attractive, useful interface. You'll create buttons and position them in the interface, so they would be ready for scripting. 2. Close the 03End.swf file. 3. Double-click the 03Start.fla file in the Lesson03/03Start folder to open the initial project file in Flash. 4. Choose File > Save As. Name the file 03_workingcopy.fla, and save it in the 03Start folder. Saving a working copy ensures that the original start file will be available if you wish to start over.   Importing Illustrator Files As you learned in Lesson 2, you can draw objects in Flash using the Rectangle, Oval, and Line tools. However, for complex drawings, you may prefer to create the artwork in another application. Adobe Flash CS3 supports native Adobe Illustrator files, so you can create original artwork in Illustrator and then import it into Flash. When you import an Illustrator file, you can choose which layers in the file to import, and how Flash should treat those layers. You'll import an Illustrator file to serve as the main component of a DVD interface.