If no object is specified, a global property of the host application itself is assumed.
This internal copy history, though, is lost after the host application is closed.
Some (often older) plugins rely on the host application for their UI.
Plug-ins depend on the services provided by the host application and do not usually work by themselves.
Most effects can be applied to a separate layer, giving users added control over the effect in the host application.
In the host application the user label input is transformed into a bit-map representation.
Downloading of any external resource from the Internet happens after notification of the host application.
Later they adopted a more modular approach and were split into a host application and an engine.
It might have Imports (dependencies) on components the host application offers, and it's likely to Export others.
Standalone services may also be created without a host application.