RasMol2 is a molecular graphics program intended for the visualisation of proteins, nucleic acids and small molecules. The program is aimed at display, teaching and generation of publication quality images. RasMol runs on Microsoft Windows, Apple Macintosh, UNIX and VMS systems. The UNIX and VMS systems require an 8, 24 or 32 bit colour X Windows display (X11R4 or later). The program reads in a molecule co-ordinate file and interactively displays the molecule on the screen in a variety of colour schemes and molecule representations. Currently available representations include depth-cued wireframes, 'Dreiding' sticks, spacefilling (CPK) spheres, ball and stick, solid and strand biomolecular ribbons, atom labels and dot surfaces.