Editing Chemical Abstracts Service (section)

===Registry===
{{As of|2023}}, the CAS Registry contains information on more than 200 million organic and inorganic substances, and about 70 million protein and [[nucleic acid sequence]]s.<ref>{{cite web|url=https://www.cas.org/cas-data/cas-registry |title=CAS Registry |website=www.cas.org |access-date=12 February 2023}}</ref><ref>[https://www.reuters.com/article/pressRelease/idUS242041+08-Sep-2009+PRN20090908 50 Millionth Unique Chemical Substance Recorded in CAS REGISTRY] {{Webarchive|url=https://web.archive.org/web/20090917020842/http://www.reuters.com/article/pressRelease/idUS242041+08-Sep-2009+PRN20090908 |date=2009-09-17 }}, Reuters.com</ref> The sequence information comes from CAS and [[GenBank]], produced by the [[National Institutes of Health]]. The chemical information is produced by CAS, and is prepared by the CAS Registry System, which identifies each compound with a specific [[CAS registry number]], index name, and graphic representation of its chemical structure.

The assignment of chemical names is done according to the [[chemical nomenclature]] rules for ''CA'' index names, which is slightly different from the internationally standard [[IUPAC nomenclature|IUPAC names]], according to the rules of [[IUPAC]].