There are three types of document variable options that may be created.
Default Variables: allow users to create document variables the program does not already have. Dates or amounts are common variables a user needs to create.
Format Existing: allows users to format variables to print in different wording or formats. Most often used to change the way a name, date or dollar amount prints.
Formula Variables: allow users to create formulas using document variables to get a specific date or dollar amount.