Basically there have been three strains of research on computer-supported argumentation.  The first and perhaps oldest is work on visualizing arguments and relationships between arguments in various kinds of diagrams, called argument maps.  An early example is the gIBIS system, by Jeff Conklin, which was a diagramming tool for Horst Rittel's "issue-based information system" (IBIS) conceptual model of argument. The IBIS model is a conceptually very simple, semi-formal model of argument, consisting of only three elements (issues, positions and arguments) linked together into graphs. The IBIS model is still quite popular, indeed the de facto standard, for "sense-making" applications of argument mapping tools aiming to help groups of people to better understand arguments.  A modern example of such a tool is Compendium.  For a good overview of the topic of argument visualization, see (Kirschner, et. al, 2003).

The second strain of computer-supported argumentation research aims to develop groupware, typically for the World-Wide Web, which helps people to deliberate more effectively.  These systems typically are some kind of discussion forum, with special support for argumentation. Systems of this kind include Zeno (Gordon & Richter, 2002) and Cohere (Buckinghum-Shum, 2008).  These kinds of computer-supported argumentation systems have often been used to support e-participation, e-democracy and policy deliberation application scenarios (Macintosh, Gordon & Renton, 2009).

Finally, the third strain of research is on the topic of more formal computational models of argument.  This research is part of the field of Artificial Intelligence and has a strong grounding in formal logic.  Computational models of argument aim to provide a formal account of such questions as what it means for an argument to be acceptable, given a set of conflicting arguments, as well as argumentation dialogues, modeled as formal games.  For good overviews of this topic, see the book "Argumentation in Artificial Intelligence" or the special issue on argumentation of the Artificial Intelligence Journal, edited by Trevor Bench-Capon and Paul Dunne.

The ambition of the IMPACT project is to develop an argumentation toolbox which builds upon all three of these strains of research, to realize a state-of-the-art argumentation toolbox for supporting policy deliberations on the Web.

Bench-Capon, T.J.M. and Dunne, P.E. Argumentation in Artificial Intelligence. Artificial Intelligence 171, 10-15 (2007), 619-641.

Buckingham-Shum, S. Cohere: Towards Web 2.0 argumentation. Computational Models of Argument – Proceedings of COMMA 2008, (2008), 97-108.

Conklin, J. and Begeman, M.L. glBIS : A Hypertext Tool for Exploratory Policy Discussion. ACM Transactions on Information Systems 6, 4 (1988), 303-331.

Gordon, T.F. and Richter, G. Discourse Support Systems for Deliberative Democracy; eGovernment: State of the Art and Perspectives (EGOV02), Springer Verlag (2002), 248-255.

Kirschner, P.A., Buckingham-Shum, S.J., and Carr, C.S., eds. Visualizing Argumentation: Software Tools for Collaborative Education and Sense-Making. Springer-Verlag, London, 2003.

Macintosh, A., Gordon, T.F., and Renton, A. Providing Argument Support for E-Participation. Journal of Information Technology & Politics 6, 1 (2009), 43-59.