The Department of In Silico focuses on understanding biological systems by computational analyses of large-scale data such as genome sequence, gene expression data and protein structures. It is a well-known fact that traditional biology has tried to enumerate as many biological phenomena as possible, resulting to thicker and thicker textbooks. Although the increase of biological information is quite useful to improve our understanding of biological systems, the increase of information makes it quite difficult to deduce useful information from raw experimental data. In other words, better data analyses are needed to lead us to a better understanding of biological systems. These considerations help us to develop new algorithms and to apply them to analyze large-scale data in this “big bang” era of biological information.