Serving static content from a cookieless domain is a standard performance best practice, one you’ve surely encountered if you’ve used a performance analysis tool like YSlow or Page Speed. The concept is simple—don’t serve static content like images and stylesheets from a domain that sets cookies—but exactly how to achieve this might not be clear to everyone. And for beginners, both the concept and the execution can be slightly confusing. So here is a brief explanation of the idea, followed by a few options for implementing it.

via Serving Static Content from a Cookieless Domain – ravelrumba.