Allow your visitors to social login and register to your Craft website using their favorite web service. When registering with a social provider, the user's profile is automatically filled with the data retrieved from his social account. You can decide which social account fields will map with Craft user fields through config variables.
In addition to providing social login to front-end users, Social plugin also provides social login to users with access to the control panel.
The Craft 2 version of the Social plugin is available on GitHub.
Support & updates for the Craft 2 version until December 2018.