Either “cc” or “xc” may be used to indicate that individuals other than the recipient of the business letter also received copies. However, “cc” is the default setting for electronic correspondence, leading to a popular preference for this abbreviation.
The distinction between these two abbreviations is that “cc” initially referred to individuals receiving a “carbon copy” of a letter sent from one person to another, whereas “xc” was coined to indicate that recipients were receiving a copy of the letter generated using a Xerox machine. Today, carbon paper is rarely used in business, although it is also true that duplicates of communication are frequently generated with copiers not manufactured by Xerox.
