When testing a website to check it’s speed score and load time using the popular tools such as Gtmetrix, Pingdom and Google Page Speed, sometime we will get a low score in “Remove Query Strings from Static Resources”. URLs which contain special characters such as question marks (? ) and ampersand (&) are treated as Query Strings. Some proxy caching servers cannot cache the resources with special character in the URL, like : http://yoursite.com/wp-content/themes/yourtheme/css/style.css?ver=1.1.1.