Planimate models are hierarchically arranged. The top level of every model is a panel called <main>. You can place portals on this panel. Each portal will have its own panel "under" it. Portals can then be placed on these panels, each will provide yet another panel, etc.
When editing a model, the hierarchy of a model is displayed in the sidebar.
Portal Attributes, Tables and Label Lists can be defined at any Portal in a model. They will then be accessible within panels inside that portal and within any other portals/panels therein.
The parts of a model where an attribute/table is available, or "visible" is called its scope and if a given location can access an attribute, it is said to be in scope at that location.
Generally scope will follow the hierarchical structure of the model but there is an exception. If a portal has a portal attribute defined and a portal within it also has the same attribute name defined, then the inner name will "cover up" access to the portal attribute defined higher up in the hierarchy.