Chemical Abstracts Service (CAS), a division of the American Chemical Society and a source of chemical information, has launched a new, free, web-based resource called Common Chemistry. This resource is helpful to non-chemists and others who might know either a chemical name or a CAS Registry Number of a common everyday chemical and want to pair both pieces of information. Common Chemistry contains approximately 7,800 chemicals of widespread and general interest, as well as all 118 elements from the periodic table. Common Chemistry provides access to information on chemicals of general interest. The full CAS REGISTRYSM database contains more than 46 million organic and inorganic substances.