HTTP/1.0 headers, continued
Expires - sent by server
- Expires: Thu, 01 Dec 1994 16:00:00 GMT
- primitive caching expiration date
- cannot force clients to update view, only on refresh
From - sent by client
- From: gribble@cs.berkeley.edu
- not really used
If-Modified-Since - sent by client
- If-Modified-Since: Sat, 29 Oct 1994 19:43:31 GMT
- server returns data if modified, else “304 Not Modified”