* '''Services''' - The services layer connects bundles in a dynamic way by offering a publish-find-bind model for plain old Java objects.

* '''[http://zenit.senecac.on.ca/wiki/index.php/OSGi_Concepts_Bundle_Life-Cycle Life-Cycle]''' - The API to install, start, stop, update, and uninstall bundles.

* '''[http://zenit.senecac.on.ca/wiki/index.php/OSGi_Concepts_Execution_Security Security]''' - The layer that handles the security aspects.

* '''[http://zenit.senecac.on.ca/wiki/index.php/OSGi_Concepts_Execution_Environments Execution Environments]''' - Defines what methods and classes are available in a specific platform.