It was a pleasant surprise to hear that Biological Se.quence. Analysis was be-ing translated into Chinese, twelve years after its first publication in 1998. Atthe time we wrote this book, SRE,
AK, GJM and I were all trying to understanclhow standard sequence alignment and analysis methods of the time worked, andto some extent we wrote the book to help us get things straight in our
ownminds. In the process we came to the conclusion that it should be possible to pro-vide a more coherent view of sequence alignment and alignment-based bioinforma-tics. At that time we had
been struck by the elegance of some new ideas in thefield, such as the application of hidden Markov models to generate protein familymultiple alignments, and stochastic context-free grammars to
reprcsent the sec-ondary structure in RNA families, and we aimed to take ideas from these meth-ods into bioinformatics more generally. With these points in mind, we started thewriting of this
book, focusing mainly on the principles of scqucnce analys ratherthan providing a common practical manual of sequence﹀ analysis tools.
The completion of the Human Genome Project was an important milcstonc inthe development of biological science. It marked the actvent of the genome era,which has changed the nature of biological
research. The great dcmand for pow-erful analysis methods to interpret the sequence coming from large genome pro-jects promoted the flourishing of computational biology, bringing in many
newpeople from a diverse set of backgrounds. Qur book turned out to become a use-ful introductory text for students and researchers with a mathematical or compu-tational background who were
interested in the field. It is very satisfying that itstill serves this purpose well, despite being over ten years old: sound fundamen-tal concepts never go out of date.
We would like to thank Jun Wang and all the other members in the BGl﹀stranslation group for their dedicated effort to translate this book into Chinese,enabling it to be introduced to a new
group of nascent bioinformaticians. In parti-cular, we wish to thank Weimou Zheng and Huimin Xie for their review of theChinese version.
