A quickly increasing amount of biological data, such as DNA/RNA and protein sequences, determines fundamental role of biological databases for functional comparative analysis of genomes/metabolic pathways of various organisms. This is neatly illustrated by ?Databases', the new type of scientific journal that has recently appeared. The journal is dedicated to bioinformatic data processing and storage. Biological databases and platforms play a crucial role in the development and progress of the systems biology. Systems biology integrates key elements of an organism functions e.g. gene and protein content, regulation of gene expression, enzymes activities, and specific profiles of different metabolites. Therefore, it is possible to generate a holistic and integrated model of basic biological functions and processes that determine an organism phenotype.