LinkedIn is a social network for professional networking. It has over 227 million members worldwide and grows by 2 new members per second. The site allows users to create a professional profile, connect with colleagues and peers, find new jobs, and promote their business. The free basic account allows users to search profiles, request recommendations, and send 5 introductions. Premium paid accounts provide additional features like the ability to see who has viewed your profile and send unlimited messages. Users are encouraged to keep their profiles and interactions on the site professional in nature.