The Work Folder Dictionary is a grouping table that directly corresponds to the Work Folders that affiliate Individual contact records to the records of the Companies for whom they work, or that they represent. The resulting connection to the Work Folder Type and Role fields in the AMS is seen in the next screen shot. 
The Work Folder Dictionary defines the “Work Position Codes” GroupType as seen in the next screen shot.
The GroupCodes and MasterCodes under the POSITION GroupType populate the drop down menu choices for the Type and Role fields, highlighted in the AMS screen shot above, that Individual contacts choose from when creating a Work Folder, or when editing their Role if it changes. Examples of common MasterCodes under an Executive Positions GroupCode are seen in the next screen shot.
More information on Work Folders is in the Profile section on Folders.