| Top Level | The Top Level package contains the core ActionScript classes and global functions. |
| flash.display | The flash.display package contains the BitmapData class for image manipulation. |
| flash.external | The flash.external package contains the ExternalInterface class. |
| flash.filters | The flash.filters package contains classes for the filter effects that are new in Flash Player 8. |
| flash.geom | The flash.geom package contains geometry classes, such as Point, Rectangle, and Matrix, that support the BitmapData class and the bitmap caching feature, which is new in Flash Player 8. |
| flash.net | The flash.net package contains classes for uploading and downloading files. |
| flash.text | The flash.text package contains the TextRenderer class, which lets you set the quality used by advanced anti-aliasing and define custom settings for fonts used by advanced anti-aliasing. |
| mx.lang | The mx.lang package contains the Locale class, which supports multilanguage text. |
| System | The System package contains the capabilities, the input method editor (IME), and security classes. |
| TextField | The TextField package contains the StyleSheet class for applying CSS styles to text. |
