Social login

Social login, also known as social sign-in, is a form of single sign-on using existing information from a social networking service such as Facebook, Twitter or Google+, to sign into a third party website instead of creating a new login account specifically for that website. It is designed to simplify logins for end users as well as provide more and more reliable demographic information to web developers.

Social login is often considered a gateway to many of the recent trends in social software and social commerce because it can be used as a mechanism for both authentication and authorization.

Social login links logins to one or more social networking services to a website, typically using either a plug-in or a widget. By selecting the desired social networking service, the user simply uses his or her login for that services to sign on to the web site. This in turn negates the need for the end user to remember login information for multiple electronic commerce and other websites while providing site owners with uniform demographic information as provided by the social networking service. Many sites which offer social login also offer more traditional online registration for those who either desire it or who do not have an account with a compatible social networking service (and therefore would be precluded from creating an account with the website).

Social login can be implemented strictly as an authentication system using standards such as OpenID or SAML. For consumer websites that offer social functionality to users, social login is often implemented using the OAuth standard. OAuth is a secure authorization protocol which is commonly used in conjunction with authentication to grant 3rd party applications a "session token" allowing them to make API calls to providers on the user’s behalf. Sites using social login in this manner typically offer social features such as commenting, sharing, reactions and gamification.

While social login can be extended to corporate websites, the majority of social networks and consumer-based identity providers allow self-asserted identities. For this reason, social login is generally not used for strict, highly secure applications such as those in banking or health.

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Wikipedia