YSlow
I was testing some of my websites using Yahoo's YSlow and noticed the following comment:
Specify an expiration at least one week in the future for the following resources
My .htacces file contains the following code:
ExpiresActive On
ExpiresDefault "access plus 1 day"Is this the best way to do it? And Why does YSlow advice you to set the cache for at least one week?
Because they consider (and it's not a bad idea) that one day is not quite long enough : if you have some user that comes to your website only a couple of times per week, a cache of 1 day will not be useful for him.
Instead, the basic idea is to cache forever -- and to change the URL (changing the name of the file, typically) when a file is modified, to force the browse to download the new version.