Most websites are coded by gifted amateurs, but Google has outdone themselves helping all webmasters automatically provide a better experience for their users. This technology brings the skills of the world's best coders to every website on the planet. Yay!
Official Google Webmaster Central Blog: Page Speed Service - Web Performance, Delivered.: "Page Speed Service is an online service that automatically speeds up loading of your web pages. To use the service, you need to sign up and point your site’s DNS entry to Google. Page Speed Service fetches content from your servers, rewrites your pages by applying web performance best practices, and serves them to end users via Google's servers across the globe. Your users will continue to access your site just as they did before, only with faster load times. Now you don’t have to worry about concatenating CSS, compressing images, caching, gzipping resources or other web performance best practices."