A content delivery network or content distribution network (CDN) is a geographically distributed network of proxy servers and their data centers. The goal is to distribute service spatially relative to end-users to provide high availability and high performance. CDNs serve a large portion of the Internet content today, including web objects (text, graphics and scripts), downloadable objects (media files, software, documents), applications (e-commerce, portals), live streaming media, on-demand streaming media, and social media sites.
Learn more: Wikipedia
How to use
Origin your statics file: http://google-analytics.com/analytics.js
Your statics file via CDN: https://iamcdn.net/trycdn?url=http://google-analytics.com/analytics.js