By including one of the Main Categories in an application‘s desktop entry file, the application will be ensured that it will show up in a section of the application menu dedicated to this category. If multiple Main Categories are included in a single desktop entry file, the entry may appear more than once in the menu.
Category-based menus based on the Main Categories listed in this specification do not provide a complete ontology for all available applications. Category-based menu implementations SHOULD therefore provide a "catch-all" submenu for applications that cannot be appropriately placed elsewhere.
The table below lists all Main Categories.
| Main Category | Description | Notes |
|---|---|---|
| AudioVideo | Application for presenting, creating, or processing multimedia (audio/video) | |
| Audio | An audio application | Desktop entry must include AudioVideo as well |
| Video | A video application | Desktop entry must include AudioVideo as well |
| Development | An application for development | |
| Education | Educational software | |
| Game | A game | |
| Graphics | Application for viewing, creating, or processing graphics | |
| Network | Network application such as a web browser | |
| Office | An office type application | |
| Science | Scientific software | |
| Settings | Settings applications | Entries may appear in a separate menu or as part of a "Control Center" |
| System | System application, "System Tools" such as say a log viewer or network monitor | |
| Utility | Small utility application, "Accessories" |
原文：http://my.oschina.net/coolfire368/blog/312525