The wcd manual: EST clustering using d2 Scott Hazelhurst School of Computer Science University of the Witwatersrand This manual describes @code{wcd} (pronounced `wicked'), a program that performs d2-clustering. Essentially, it takes a set of DNA sequences (typically Expressed Sequence Tags, ESTs), and clusters the sequences into the related groups. This manual assumes that a user understand the basic principles of what EST clustering is about, and so the basic concepts are only briefly reviewed in this chapter. Subsequent chapter discuss installing and running @code{wcd}, as well as giving some technical background so someone who wants to use some of the code.