Link building can play an important role within a search engine optimisation campaign, or as an effective stand alone service.
The primary goal of link building is to increase the relevance of your website for specific keywords. This is achieved by linking to your website from other websites using the chosen keywords as the anchor text.
When a search is performed for those particular keywords, your website will be classified as being relevant and the search engines will rank you accordingly.
Visit the search engine optimisation pages for more information on how it can benefit your website.