Studies have shown that website registration forms are inefficient as many people provide false data, forget their login information for the site or simply decline to register in the first place. A study conducted in 2011 by Janrain and Blue Research found that 77 percent of consumers favored social login as a means of authentication over more traditional online registration methods. Additional benefits: ; Targeted Content : Web sites can obtain a profile and social graph data in order to target personalized content to the user. This includes information such as name, email, hometown, interests, activities, and friends. However, this can create issues for privacy, and result in a narrowing of the variety of views and options available on the internet. ; Multiple Identities : Users can log into websites with multiple social identities allowing them to better control their online identity. ; Registration Data : Many websites use the profile data returned from social login instead of having users manually enter their
PII (Personally Identifiable Information) into web forms. This can potentially speed up the registration or sign-up process. ; Pre-validated Email : Identity providers who support email such as
Google and
Yahoo! can return the user's email address to the 3rd party website preventing the user from supplying a fabricated email address during the registration process. ; Account linking : Because social login can be used for authentication, many websites allow legacy users to link pre-existing site account with their social login account without forcing re-registration. ==Disadvantages of social login==