By using several PAGE SPEED LOAD analyzing tools (last but not least the YSlow add-on for Firebug) I noticed that one of main concern of most of my websites is the "Leverage browser caching" issue. That specifical issue is explained by the output of the tool: "Reduce the load times of pages by storing commonly used files from your website on your visitors browser." The following cacheable resources have a short freshness lifetime. Specify an expiration at least one week in the future for the following resources: http://www.mysite.com/wp-content/themes/theme-name/css/stylename.css (expiration not specified) http://www.mysite.com/wp-content/themes/theme-name/images/icons-header.png (expiration not specified) http://www.mysite.com/wp-content/themes/theme-name/images/background_1.jpg (expiration not specified) AND SO ON... The list goes on for at least 30+ resources. The strange thing is that if I run the same tool on SitePoint.com or similar trusted site I get the same kind of error. What do you think guys?