Word's sample templates often use the specially set up Document Property Content Controls. You can do the same thing. These are built-in Mapped Content Controls that you can repurpose.
Repeating Data Using Document Property Content Controls and Other Mapped Content Controls
Greg Maxey has a number of pages on using Content Controls, especially
Mapped Content Controls. He discusses the built-in ones in his pages
Enhanced Document Properties AddIn and
Repeating Data (Populating Multiple Like Fields) by Greg Maxey.
Addressing your question in the title: Content Controls are not
fields, although they can be used inside fields. Paul Edstein has posted several excellent tutorials on fields that are pinned to the top of
this forum as well as the
Mail Merge Forum. Graham Mayor has a number of articles about fields on
his site. I especially like his Add-In
http://www.gmayor.com/export_field.htm.