Always save a new Adobe Flash Creative Suite 5 document after you make significant changes or additions to it, and always save (though it isn’t necessary) a new Flash CS5 document immediately after you create it.

To save a document, choose File→Save. Enter a name for the file and choose a location on your hard drive to save it. You can save Flash work files in .fla format or the new .xfl file format.

You may need at some point to save a copy of your document under a new name, to either create an alternative version or perhaps make it compatible with an older version of Flash. Flash CS5 can save .fla files in CS4 format to make it compatible with the previous version of Flash.

Flash CS4 can’t open .xfl or Flash CS5–format .fla files. To share a file with someone using Flash CS4, choose File→Save As→Flash CS4 Document (*.fla).

To save a copy of your document under a new name, choose File→Save As. Choose a location on your hard drive and enter a new filename. The drop-down list at the bottom of the Save As dialog box lets you choose in which version of Flash to save the file. For example, you can save files one version earlier into Flash CS4 format.

If you used previous versions of Flash, you probably noticed that Flash CS5 features a new file format: .xfl. Thus new, uncompressed file format results in a project folder containing a number of .xml files and any original assets (such as images and audio files) that you may have imported into your project’s library.

Because of this open file format, resources in your project can be exchanged with and opened in other applications. The XFL file format opens up the possibility of Flash files eventually being editable in other applications.

The traditional FLA file format combines all your project’s vital information and resource files into a single file, making it more portable but less likely to exchange with other applications. You don’t have direct access to assets you’ve imported into your project; for most purposes, however, the standard FLA file format is suitable, especially if Flash CS5 Professional is your sole editor for Flash applications.

Saving a document in an older version of Flash may make some newer features unavailable. Avoid saving files in an older file format unless you absolutely need to make them available to an older version of Flash.