Content delivery networks (CDNs) are composed of "edge
cache" servers that are strategically placed around the world at key
Internet network points. These "edge cache" servers can be used
to cache and deliver all types of content – including images, videos, CSS and
Using a CDN can significantly improve a website's end-user
performance, since it enables browsers to more quickly retrieve and download
content. For example, instead of having a browser request for an image
traverse all the way across the Internet to your web server to download, a CDN
can instead serve the request directly from a nearby "edge cache"
server that might only be a single network hop away from your customer (making
it return much faster – which makes your pages load quicker).