Differences between Modules, Plugins, Extensions, and Expansions
ExpressionEngine includes different types of add-ons:
- Plugins are small run-time enhancements. They are simple to create.
The plugin architecture is designed to enable the plugin’s author to
affect the output of ExpressionEngine in a wide variety of ways.
- Modules are larger systems that can be integrated into the
ExpressionEngine control panel. Almost anything that can be achieved
as a stand-alone application can be designed as an ExpressionEngine
module. Modules typically store content in the database and can have
actions associated with them.
- Extensions are “hooks” in the system that allow the add-on to pass
information and add functionality to existing interfaces.
- Expansions add a new layer of functionality to ExpressionEngine.
There is only one expansion: the Multiple Site Manager.