For search engines that crawl the web, links are the streets between pages. Using sophisticated link analysis, the engines can discover how pages are related to each other and in what ways.
Since the early says of Search Engines links have been used as a major ranking factor, they basically act as votes for the site. Back in the early days it was quite simple, more links meant better rankings. Unfortunately as you can imagine people realised this and exploited it by generating thousands of links from various techniques such as link networks, reciprocal links and directories.
Therefore Search Engines are always in a constant battle with spammers, trying to refine their algorithms to ensure the search engine results are as accurate as possible. Nowadays it is not just about the volume of links a website receives but about the quality of a link. For example a link to a mobile phone deal on a phone website from an article about cheap phone deals off a reputable gadget site such as Engadget will have considerably more effect than dozens of links back from newly set up blogs with spammy articles.
At Dolphin Promotions we will help you develop a link building strategy and work closely with you to try and get quality links. This will often include regular blog posts on your site, competitions, guest posts on other peoples sites and using local directories.