304 Not Modified is a HTTP status code that indicates that the requested resource has not been modified since the last time it was accessed, therefore there is no need to retransmit the requested resources.
The 304 Not Modified client redirection response code is sent by the server in response to a conditional GET request, when accessing a cached resource.
This status code indicates that the cached version is up to date and should be used by the client instead, which saves bandwidth.
304 Not Modified redirects can be easily executed in All in One SEO (AIOSEO) by using the plugin's Redirection Manager.
Related: