RFC /R-F-C/ n.
[Request For Comment] One of a long-established series of numbered Internet informational documents and standards widely followed by commercial software and freeware in the Internet and Unix communities. Perhaps the single most influential one has been RFC-822 (the Internet mail-format standard). The RFCs are unusual in that they are floated by technical experts acting on their own initiative and reviewed by the Internet at large, rather than formally promulgated through an institution such as ANSI. For this reason, they remain known as RFCs even once adopted as standards.
The RFC tradition of pragmatic, experience-driven, after-the-fact standard writing done by individuals or small working groups has important advantages over the more formal, committee-driven process typical of ANSI or ISO. Emblematic of some of these advantages is the existence of a flourishing tradition of `joke' RFCs; usually at least one a year is published, usually on April 1st. Well-known joke RFCs have included 527 ("ARPAWOCKY", R. Merryman, UCSD; 22 June 1973), 748 ("Telnet Randomly-Lose Option", Mark R. Crispin; 1 April 1978), and 1149 ("A Standard for the Transmission of IP Datagrams on Avian Carriers", D. Waitzman, BBN STC; 1 April 1990). The first was a Lewis Carroll pastiche; the second a parody of the TCP-IP documentation style, and the third a deadpan skewering of standards-document legalese, describing protocols for transmitting Internet data packets by carrier pigeon.
The RFCs are most remarkable for how well they work -- they manage to have neither the ambiguities that are usually rife in informal specifications, nor the committee-perpetrated misfeatures that often haunt formal standards, and they define a network that has grown to truly worldwide proportions.