What is "social bookmarking"? and how can it benefit my social media marketing strategy?

Social bookmarking is a tool that allows you to add tags and comments to your bookmarks.

Bookmarks show how a site is perceived, and when these sites allow voting, they also show the engines or whatever classification system which monitors voting, how people feel about the quality of the site. Furthermore, social bookmarking can introduce a site to the search engines, as in some cases, people may find and bookmark a site or a site’s internal pages before a search engine can find those pages via another form of inbound link.