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Binomial nomenclature names an organism with a capitalized genus followed by a lowercase species epithet; both are italicized in print, while handwritten names are underlined. After the first full mention, the genus may be shortened to its initial and a period, but the species epithet remains written out. Family and order names use characteristic endings and remain in roman type, as do strain and other descriptors following a species name. The topic also introduces abbreviations such as sp. and spp., provisional names beginning with Candidatus, and differences in how viruses are named. International codes govern names in different organism groups, while valid publication and approval are relevant to bacterial names and taxonomic changes. These conventions help readers interpret names consistently without confusing organisms, classifications, or disease names.