dotmatcher. A Dotplot image: C. elegans and C. briggsae sequences are placed on the axes. The gene structure generated on the fly help the Investigator to orient itself in the rectangular image. The top of the image shows parameters given by the investigator (windowsize and threshold). This web images are clickable by the user, the single click is extended in both directions for n base pairs. Both segments (one for C. elegans and one for C. briggsae) are sent to the Ssearch control page, in order to align segments with the Smith and Waterman algorithm.