URL indicating document sections: Is it possible to specify a particular section when opening a PDF document or an HTML page via a URL?
Yes, this is possible. For PDFs use, for example

http://www.example.com/myfile.pdf#page=4

For HTML documents there is no page structure but you can define an HTML "anchor" element <A name="anchor-one">This is anchor one.</A>

You then name the anchor element in the URL. Example:

http://www.mycompany.com/one.html#anchor-one