Scientists use two names to describe each kind of bacteria. The first is the genus name and second is the species name. When the names of the species and genus are written, the are italicized, or underlined. The genus name usually refers to the group to which the bacterium belongs, somewhat like our human family names, except it is listed first. Many times the genus and species names (in the Latin or Greek language) are selected to describe some general feature of the bacterium.