CloudFlare makes websites faster and more secure.  When you put your website on CloudFlare, we distribute the content globally in a CDN like fashion.  Security comes in the form of a Web Application Firewall;  CloudFlare is able to filter out "bad" traffic leaving you with a more secure website.

Our network is a global anycast network.  We announce several global /24s which serve CDN traffic.  We determine the scope of routes to send you based upon your network's scope and footprint in relation to our point of interconnect.