Social book marking is a relatively new phenomenon on the internet. Basically, an individual saves web pages or web sites that they like to a second website where they can share this information with others. Social bookmarks are considered highly reliable since they are not based on paid advertisements, but true opinions of other web users. Examples of social book marking sites include del.icio.us, Blue Dot, Diigo, Furl, My Web (Yahoo!), Netvouz, Simpy, StumbleUpon, Kaboodle and BibSonomy. All of these sites provide different features, but the applications are basically the same.
When users book mark your site, they are creating a new link to your site, creating more links. Second, these links expose your site to new users with similar interests, increasing your traffic and customer base.
You can increase the number of users that book mark your site by giving them the tools to bookmark your web site. A simple link, or even a web page that allows users to easily add your site to their book mark list is often all that is needed. Visit the websites listed above, and make yourself familiar with how they work. Many of these sites will offer tools to you to help increase your visibility on their site.