It sounds as if someone has created custom heading styles with these names.

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Suzanne S. Barnhill
Microsoft MVP (Word)
Words into Type
Fairhope, Alabama USA
Word MVP FAQ site: http://word.mvps.org
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> I have a document that many others have worked in that is
> displaying it's style as Style Heading x as opposed to
> Heading x. What is the difference and how did it become
> the style of "Style Heading x"? My documents are
> typically set up to use the heading styles for numbering.