HumHub - Open Source Social Network
HumHub is a feature rich and highly flexible OpenSource Social Network Kit written in PHP. It provides support to build Social Intranets, Enterprise Social Networks, Private Social Networks. Its social features include Commenting, Like, Following, Mentioning, Tags, OEmbed Support. The communication in HumHub works with spaces. A space can literally be anything, a project, a group or just a simple topic. For every space you can invite multiple users and make up your own access rights and rules.