I’ve worked in the CDN industry for several years now.  Every time I talk to a person that is not in the CDN industry or hasn’t had any experience with a CDN (surprisingly this happens a lot in the Silicon Valley) they obviously ask me, “what is a CDN?”

A CDN is short for a Content Delivery Network.

Now, you’re probably thinking, “great, I still don’t know what  that means!”  That’s OK, most people still need me to explain it, so I will.

A CDN, or Content Delivery Network, is a network of servers that have been placed around the world to help deliver content over the Internet as fast as possible.  There are several companies that have built these networks and charge access to use their network to deliver the content.

The reason that content delivery networks were created is due to the speed of light.  Without going into a whole dissertation into this, basically content such as websites, images, videos is delivered over fiber networks that use light.  According to physics, light only moves so fast and therefore, the farther away that you get from the original source of the content, the longer it will take for that content to get there.  This is where the network of servers come into play.

A content delivery network will take the original content from the webserver that it’s hosted on and cache it (copy it) and place it on multiple servers around the world.   By doing this the networks are moving the content closer to the end viewer and reducing the amount of time it takes to get deliver the content down to the end viewer.  There’s a lot more to this, but this is the gist of how content delivery networks generally help deliver content faster to the end user.

Nearly every major website you visit uses a CDN.  This is especially true for eCommerce websites like Amazon.com.  Amazon has published many reports that show that the speed of their website is directly correlated to their sales – the slower the website, the less they sell.  Other companies have also published reports showing that the faster a website is the more readers will stick around and read a website.  If you want to make sure your website viewers are having a great experience, then you too will want to use a CDN.

As I mentioned above, there is a variety of content delivery networks out there, but I typically use MetaCDN due to their ease of use and low cost.  They currently power most of my websites and videos.