Posted by John Kelly on 09/24/06 21:28

Pardon me if this is a FAQ. I searched, but got far too many hits to
find the answer. Question:

Why is the date: Thu, 19 Nov 1981 08:52:00 GMT used as the value for
anti-caching Expires: headers?

Why not use the UNIX epoch of Thu, 01 Jan 1970 00:00:00 GMT?

The IBM PC debuted in 1981, but that was August 12, not November 19.
Is there a PC clock "epoch" related to the November 19 date used by
PHP?

[Back to original message]