|  | Install: <module>_installer::install() is called, any necessary tables
are created.
Activate: <module>_installer::activate() is called.  Module
controllers are routable, helpers are accessible, etc.  The module is
in use.
Deactivate: <module>_installer::deactivate() is called.  Module code
is not accessible or routable.  Module is *not* in use, but its tables
are still around.
Uninstall: <module>_installer::uninstall() is called.  Module is
completely removed from the database.
Admin > Modules will install and activate modules, but will only
deactivate (will NOT uninstall modules). |