Flash9:Save

Flash provides several save options
 * Save - fast save fla file in memory
 * Save As - make a copy - you should use this for version control
 * (hints:)
 * I add v1, v2 after the file name to help manage the versions then add the current date to the start of the version I just copied in year month day format (eg. 20081031MyMovieV1.fla).
 * Always use the new copy to work on.
 * Save and Compact - removes assets marked for deletion in current project

In order to speed up the save library assets are appended to the current fla file, and if you delete an existing library asset it is marked for deletion (not removed), so saving the file will not reduce its size.

To remove assets and therefore decrease the size of your fla movie, use Save As or Save and Compact.

Adobe (n.d.)