Flex Modules are code functionality compiled to dynamically-loadable SWF files that can be loaded and unloaded by an application at run-time.
Modules let you split your application into several pieces, or modules. The main application, or loader, can dynamically load other modules that it requires, when it needs them. It does not have to load all modules when it starts, nor does it have to load any modules if the user does not interact with them.
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