Yes, social media is now providing great help for business websites. Google is also giving those more importance in SERPs by providing the pages and links in related search results. Social media marketing in a boom position now and a huge mass of online visitors using and participating in Social media like Facebook, Linkedin and Twitter etc.
Sorry, but this is far too vague a question, as a simple search would have sufficed to answer the question. Please search (both the forums and via your favorite search engine), and if you've still got SPECIFIC questions, please feel free to repost.