Abstract
This chapter describes how computers played a decisive role in the sequencing and understanding of the genomes of humans and other organisms. The discovery of the structure of DNA, by Watson and Crick, opened the way to a systematic approach to biology, based on the study of the way DNA encodes the proteins in all living cells. The area that became known as computational biology, or bioinformatics, aims at modelling, simulating, and understanding the behaviour of biological systems, using computer models and algorithms. Such a deep understanding will enable us to create computer models of cells and of entire organisms and even, in the future, open the doors to the creation of entirely new lifeforms, a field known as synthetic biology.