Last-Modified
| Last-Modified |
The Last-Modified header tries to provide information about the last time this entity was changed. This could mean a lot of things. For example, resources typically are files on a server, so the Last-Modified value could be the last-modified time provided by the server's filesystem. On the other hand, for dynamically created resources such as those created by scripts, the Last-Modified value could be the time the response was created.
Servers need to be careful that the Last-Modified time is not in the future. HTTP/1.1 servers should reset the Last-Modified time if it is later than the value that would be sent in the Date header.
Type
Entity header
Basic Syntax
Last-Modified: HTTP-date
Example
Last-Modified: Thu, 03 Oct 1997 17:15:00 GMT