Social bookmarking is a way for users to store and organise bookmarks of web pages. In a social bookmarking system, a user will save a link to web pages that they want to remember and/or share. There are a number of third party services offering social bookmarking facilities, vBulletin provides the ability to link directly to an add page and pre-populate the data.
When a user views a publicly accessible thread they will be presented with a set of links at the bottom which allow the addition of the page to admin defined social bookmarking sites.