Facebook - Connect with friends, family and other people you know. Share photos and videos, send messages and get updates.
Elgg - Opensource social network engine
Minds - The open-source, encrypted social network that expands your reach for using it.
HumHub - HumHub is a free social network software and framework built to give you the tools to make teamwork easy and successful.
Diaspora - The online social world where you are in control.
SocialEngine - eXo Platform