Ajax but like native for browser and for Google(fully SEO friendly). URL changed. Back browser button work. Links are absolute – looks same for Google. Saving server power, saving customer traffic. Saving bandwidth. All it makes site as fast as it can be. Also great core structure to work fast. User from Google will come directly to indexed product page, not to homepage – all links are working and without Ajax. Say users come to site first time and all links are Ajaxfied for user from any page. Also tested with tens of thousands of products and still fast.