From the about page:
AGORA-net is a Computer-Supported Collaborative Argument Visualization (CSCAV) tool. An argument is defined here as a set of statements—a claim and one or more reasons—where the reasons jointly provide support for the claim, or are at least meant to support the claim.
AGORA-net can be used for free by everybody. The software provides step-by-step guidance to construct arguments and networks of arguments and counter-arguments. The software is collaborative in the sense that users can work simultaneously on the same argument map via an internet connection, be it in face-to-face communication or online. They can add arguments and objections to statements, as well as references, links to resources, comments, definitions, and friendly amendments.
The design of an AGORA-net argument map is based on the consideration that the main point of arguing is to provide a justification for a claim, a thesis, or a recommendation. Thus, these statements are always located on the top left of your screen. By providing reasons for your claim, you work to the right. Of course, any map can be read from any direction.
Here is an example AGORA argument on the topic of millennial voting:
Existing public AGORA arguments can be found in their index divided into topics. If a user is logged in, they are able to contribute to existing arguments as well as view their maps, projects, and contributions. There is also a search tool to parse through existing arguments. Below is a 5-minute introductory video on constructing an AGORA argument:
Additional instructions on how to use AGORA can be found on their What You Should Know Before You Start page. AGORA-net is available in English, Russian, German, and Spanish.
AGORA-net was conceptualized and designed by Michael Hoffmann, Director of the Philosophy Program in the School of Public Policy at the Georgia Institute of Technology, and funded by the United States-Russia Program of FIPSE, the Fund for the Improvement of Postsecondary Education, and U.S. Department of Education (Grant P116S100006). Collaborators include Bauman Moscow State Technical University (2010-2012) and the Institute of Philosophy in the Russian Academy of Science (2012 onwards).