How do I set expiration on CSS, JS and Images?

Question

I have recently analysed my website with pagespeed addon on firebug. It suggested me to set expiration on CSS, JS and image files.

I am wondering, how do I do this?

Answer 1

This is the one I use to fix the exact same thing when I ran the PageSpeed Addon:

    Header set Cache-Control "max-age=604800, public"

This goes into your .htaccess file.

Read up on this page for more information about how to set cache for additional file types and/or change the cache length:

http://www.askapache.com/htaccess/apache-speed-cache-control.html