OPENING AN ARTICLE: If you have never used Acrobat Reader or PDF files before, please believe me -- it's painless. Everything operates in the background. All you do -- after installing Reader -- is click on the link for a PDF file and you computer does the rest. Reader will automatically spawn in a new window with the article inside it.
NAVIGATING WITHIN AN ARTICLE: In all cases, you can move from page to page using the scroll bar. You may also click on the thumbnails of the pages, or utilize the bookmarks (provided that I have established bookmarks). Bookmarks are the fastest way to move to specific sections of an article, while thumbnails are the quickest way to go to a specific page. To see the thumbnails and bookmarks, you must open the pane (or frame) that contains them. Clicking on the 4th icon from the left on the Acrobat Reader Tool bar will do this for you. Then just click on the bookmarks or thumbnails tab to utilize the one or the other.