Chapter 15. Working with Images, Sound, and Video
If you import an image or a sound while you author a document in Macromedia Flash Basic 8 or Macromedia Flash Professional 8, the image and sound are packaged and stored in a SWF file when you publish it. In addition to importing media while authoring, you can load external media, including other SWF files, at runtime. You might want to keep media outside of a Flash document for several reasons.
Reduce file size. By keeping large media files outside of your Flash document and loading them at runtime, you can reduce the initial downloading time for your applications and presentations, especially over slow Internet connections.
Modularize large presentations. You can divide a large presentation or ...