An app instance is a file that's type points to an app. Similar to a class instance in object oriented programming.
A bucket placeholder is used to define a bucket within a component.
Components are the no-code equivalents of apps. It is used to create reusable elements or element structures, typically via drag-and-drop. A component wraps one or more app or component instances and optionally declares some input files to be defined at component instances.
For example, a page component may define a page layout to have a certain menu and footer, but the contents should not be the same on all pages (instances of that page component), rather defined individually.
Components are mostly implemented in kernel space but they require certain functionality to be defined in user space. These are defined in the component app.
The file type of components points to this component app.
A component instance is similar to an app instance but for components.
Component instances encapsulate the inner structure of the referenced components and present them as single objects. Only the input parameters of the component (input files) can be defined at the component instance level.
..are resolved relative to the
/sys/packagesfile. For example, the type
gallery.boomla.net/gallerywould resolve to