Specify expires or Cache-control for the file header (bottom)

browsers (and proxies) use caching to reduceHTTPThe size and number of requests to speed up page access.WebServer inHTTPUse in responseExpiresThe file header to tell the client how long the content needs to be cached.

Using the Expires file header will only work if the user has already visited your site. This is not valid for reducing the number of HTTP requests when a user first visits your site because the browser's cache is empty. So this approach will improve the performance of your site based on how often their " pre-cache " is clicked on your page (" pre-cache " already contains all of the content on the page).

There are "pre-caches" in 75~85% in page views. By using the Expires file header, the number of cached content in the browser is increased, and the content can be reused in the user's next request, which does not even require a byte request to be sent by the user.

Specify expires or Cache-control for the file header (bottom)