The "Forums" page lists the current forums, arranged in categories. Each forum collects postings in the form of topics, which you can create. Navigate to a forum by clicking on its title.

The "Languages" category collects forums for topics about specific languages. By default it only shows the languages used in your user profile. Toggle "Show all languages" to display forums for other languages.

If you want to receive email notifications about new postings or other changes to a forum, toggle the "Watch this forum" button with the little eye icon. Toggle it again to stop watching a forum.