"A biological database is a large, organized body of persistent data, usually associated with computerized software designed to update, query, and retrieve components of the data stored within the system. A simple database might be a single file containing many records, each of which includes the same set of information."
A few popular databases are GenBank from NCBI (National Center for Biotechnology Information), SwissProt from the Swiss Institute of Bioinformatics and PIR from the Protein Information Resource.
GenBank: GenBank (Genetic Sequence Databank) is one of the fastest growing repositories of known genetic sequences.
EMBL: The EMBL Nucleotide Sequence Database is a comprehensive database of DNA and RNA sequences collected from the scientific literature and patent applications and directly submitted from researchers and sequencing groups.
SwissProt: This is a protein sequence database that provides a high level of integration with other databases and also has a very low level of redundancy (means less identical sequences are present in the database).
Related Journals of Bioinformatics Databases
Journal of Next Generation Sequencing & Applications, Transcriptomics: Open Access, Drug Designing: Open Access, BMC Bioinformatics, Briefings in Bioinformatics, Briefings in Functional Genomics and Proteomics, Comparative and Functional Genomics, International Journal of Data Mining and Bioinformatics, Current Protocols in Bioinformatics, Translational proteomics, Internet Journal of Genomics and Proteomics, Algorithms for Molecular Biology, Mathematical Biology and Bioinformatics, BMC Bioinformatics