During development, every plug-in, fragment, feature and update site is represented in the workspace by a single project. Each type of project is configured with special natures and builders to allow PDE to validate their manifest file(s).
To help you create these projects, PDE provides new project creation wizards. These wizards are accessible via File > New > Project... > Plug-in Development from the top level menu.
For details on individual wizards, refer to the following documents: