text: The modern approach is to carry out DNA–DNA hybridization in silico utilizes completely or partially sequenced genomes. The [http://ggdc.dsmz.de GGDC] and [https://tygs.dsmz.de/ TYGS] developed at DSMZ are the most accurate known tools for calculating DDH-analogous values. Among other algorithmic improvements, it solves the problem with paralogous sequences by carefully filtering them from the matches between the two genome sequences. The method has been used for resolving difficult taxa such as Escherichia coli, Bacillus cereus group, and Aeromonas. The Judicial Commission of International Committee on Systematics of Prokaryotes has admitted dDDH as taxonomic evidence.