Leverage browser caching

Question

According to: http://code.google.com/speed/page-speed/docs/caching.html#LeverageBrowserCaching I should be using browser caching. However, I don't know how.

Do I simply add certain tags into the html section? Or is thing something I need to send via to server to the client? something to do with php headers?

Answer 1

Caching is controlled via a variety of HTTP headers. You should read Mark Nottingham's Caching Tutorial for Web Authors and Webmasters. You can set HTTP headers for documents outputted from PHP using the header function.

Answer 2

You can do something like this in your .htaccess.

  ## EXPIRES CACHING ##
<IfModule mod_expires>
ExpiresActive On
ExpiresByType image/jpg "access 1 year"
ExpiresByType image/jpeg "access 1 year"
ExpiresByType image/gif "access 1 year"
ExpiresByType image/png "access 1 year"
ExpiresByType text/css "access 1 month"
ExpiresByType application/pdf "access 1 month"
ExpiresByType text/x-javascript "access 1 month"
ExpiresByType application/x-shockwave-flash "access 1 month"
ExpiresByType image/x-icon "access 1 year"
ExpiresDefault "access 2 days"
</IfModule>
  ## EXPIRES CACHING ##