Topics are general category pages to which sub-topics (where specific issues are discussed) are linked. It gives you an overview of all the sub-topics related to that general topic and you can access any of these sub-topics by clicking on the blue title. You can see all sub-topics by looking at the Sub-topics index at top. If you would like to suggest a new topic to be added go to the Discussion area and find the thread on "Suggest new topics". The admins will review and add new topics as appropriate.