Chado is a relational database schema that underlies many GMOD
 installations. It is capable of representing many of the general
 classes of data frequently encountered in modern biology such as
 sequence, sequence comparisons, phenotypes, genotypes, ontologies,
 publications, and phylogeny. It has been designed to handle complex
 representations of biological knowledge and should be considered one
 of the most sophisticated relational schemas currently available in
 molecular biology. The price of this capability is that the new user
 must spend some time becoming familiar with its fundamentals.