OC_WEB is a web interface for OC program which is a clustering program developed by Prof. Geoffrey J. Barton (Dundee University, UK). Please cite OC ( Barton, G.J. (1993, 2002) OC - A cluster analysis program", University of Dundee, Scotland, UK; www.compbio.dundee.ac.uk/downloads/oc)) if you are using this server. The OC software Package is freely available at http://www.compbio.dundee.ac.uk/downloads/oc/ . If you have any technical question on OC program then contact Prof. Geoffrey J. Barton. Please read OC manual for detail . The web interface was developed by Dr G P S Raghava .