About the Target Platform
The target platform is a directory of bundles that are made available for use within FlexBuilder. Anytime a bundle selection dialog is shown, bundles both in the current FlexBuilder workspace (i.e. ones you’re working on) and bundles in the target platform (i.e. ones you’ve downloaded) are shown. Another way to think of it… the target platform is the bucket of external or precompiled bundles.
It’s a good idea to put the target platform directory under source control. Changes to a target platform should be replicated to each member of a team.
The target platform folder is specified in Preferences. See Getting Started.
Bundles in the target platform are in their exported form. An exported bundle is a folder whose name is the same as the bundle and which contains the bundle’s SWC, SWF, and bundle.xml.

