This Class is used to negotiate the current HTTP Request response. It issues full Response headers, and can change the response depending on the Request headers sent by the browser (exactly as web-servers do for static files). It will serve load-balanced compressed output if the browser supports it & the response content type is worth it, (HTML, XML, plain text, etc.) (Accept-Encoding). It can also avoid sending content if previously sent and cached to the browser & not changed since then (304 Not Modified). It can also send a part of the content if the browser requests it (206 Partial Content). The class will send Content-Type, Content-Language, Expiry, Cache-Control Response headers, plus report the Referer, browser User-Agent & OS. The class can serve custom Error-Pages, auto-fixed for serving to MSIE browsers (404 Not Found, 410 Gone, & other). 3 lines of code to implement. All setup parameters have defaults. All defaults may be changed. < 0.002 secs. In active use.