As specified in 8.2.3 of the HTTP 1.1 specification: http://www.w3.org/Protocols/rfc2616/rfc2616-sec8.html

I found this fascinating:

celluloid/reel/issues#111

counterpoint:

http://www.fallingcanbedeadly.com/posts/http-100-continue-latency-and-you/