This is an excellent question, but, I'm sorry, I think you are expecting a bit too much, like mind reading, from a vba program. Descriptions of uses of the built-in styles fill many pages. Most are semi-undocumented. Styles are at the heart of Word and understanding them is crucial to using Word well. It is just that I don't think a vba program can do much to shortcut what you'll have to learn.

The purposes of styles are determined by the person who creates it. See Understanding Styles in Microsoft Word
Why use Microsoft Word’s built-in heading styles?
Tips for Understanding Styles in Word
How to create numbered headings or outline numbering in Word 2007 and Word 2010
3. Use styles to format text
5. Use a bulleted paragraph style for bullets and dotpoints
What happens when I send my document to someone else? Will Word mess up my formatting?
How to control the Quick Styles gallery on the Home tab in Word

I would recommend getting a good book and starting with that.
Ø Microsoft Word 2010 Bible by Herb Tyson
Ø Microsoft Word 2010 In Depth by Faithe Wempen
Ø Microsoft Word 2010 Inside Out by Katherine Murray

Ø Microsoft Word 2010: The Missing Manual by Nancy Connor and Matthew McDonald