The object palette contains simple template objects that can be dragged to the document window.
When you first start SQLEditor there are object templates for the three basic object types (tables, comments and fields/columns).
You can then add custom templates for objects and groups of objects. The object palette is shared between documents and is an easy way to keep reusable parts to hand.
Note that the new object name may change slightly depending on the objects currently in the document
Alternatively you can use the clipboard instead
The object palette is shared between all documents and the data is stored in your user preferences.
Deleting a template will remove it for all documents.
You can remove templates that you have added. However the built in templates (currently tables, fields and comments) cannot be removed