Non-dictionary vs. dictionary entities
The "Create entity" dialog is the "Has dictionary" toggle, which allows you to create entities with or without a dictionary.
"Has dictionary" toggle
Whether an entity needs a dictionary depends on the specific use case.
Non-dictionary entities
Extracting predefined layout elements, a specific term, a term of a limited set of terms, or regex patterns does not require an entity with a dictionary.
Dictionary entities
If you are not searching for a specific term or a limited set of terms within your document but considering numerous potential matches, you can create an entity with a dictionary. This allows for creating rules that extract applicable dictionary matches from documents/layout elements.
For information on how to populate an entity’s dictionary, please see Create dictionary entries.