The "Up" and "Down" buttons allow the user to explore the articles by the date submitted. Articles at the bottom of the list are the newest and those at the top are the oldest. Pressing "Up" moves the user higher in the list. Pressing "Down" moves the user lower in the list.
When an article is posted, users have the chance to respond. This response creates a thread- a link connecting articles with the same topic name. Threads allow users to see the content history of a discussion.