Source can be as simple as a single field or a single tag, such as AddressBook, or #News. But it can be more than just a field / tag name, in fact it's also a filter. It's the query that indicates what items are selected for the current Grid.

For example, instead of just AddressBook you could put AddressBook and Archived is null to only show unarchived contacts.

The reason why Source and Filter are kept separate is so you can keep the Source constant as you tweak the Filter Source Filter Editbox

When a Grid is first created its Source is set to be the property that matches the Grid's name.

When the Source Box has only one field listed (sometimes called a simple Source) then any new top-level-items created in the Grid will automatically have that value set so they meet the Source criteria.

Notes:

• If the source field name contains spaces, it needs to be enclosed with [  ]
• To use tags, precede the tag name with #