Search engines use the number of links pointing to your website (backlinks) as an important measure of your website's quality and importance. Social media websites can be used to create high value backlinks that will boost your website search engine ranking.
Website backlinks strongly influence where your website is placed in search results (top of page one or bottom of page 50...). You need to create a network of websites with links back to your website to improve your website SEO.
One of the easiest ways to create backlinks to your website is to create a profile for your business on a few of the popular social media websites such as MerchantCircle, InsiderPages, or Yelp. These websites provide a free webpage with a link to your website. These websites all get high recognition in the major search engines and can provide good search result placement in the search engines for keywords in your business profile.