In punctuation, a serial comma (also called Oxford comma and Harvard comma) is a comma placed immediately before the coordinating conjunction (usually and, or, or nor) in a series of three or more terms. For example, a list of three countries might be punctuated either as “Portugal, Spain, and France” (with the serial comma), or as “Portugal, Spain and France” (without the serial comma).
Opinions among writers and editors differ on whether to use the serial comma. In American English, a majority of style guides prescribe use of the serial comma, including The Chicago Manual of Style, Strunk and White's Elements of Style, and the U.S. Government Printing Office Style Manual. The Associated Press Stylebook for journalistic writing advises against it. It is used less often in British English, but some British style guides recommend it, including the Oxford University Press's style manual and Fowler’s Modern English Usage.
Some writers of British English use it only where necessary to avoid ambiguity.
17 Feb 2013 / 13 notes