The following guide will show you how to setup Smart DNS on Mac OS X. This how-to was setup on OS X Yosemite 10.10.5 using the PureVPN Smart DNS service but other versions of OS X and providers will be similar.
What is Smart DNS?
Smart DNS is a service used primarily to unblock geo-restricted services. For example, being in the U.S. I am restricted from using the BBC iPlayer or the CBC player. Users outside of the U.S. are blocked from Netflix USA content, Spotify, and other popular services. While you can use a VPN to geo-unblock services by connecting to a VPN proxy located in the country you wish to appear to originate from, this can be less than ideal for streaming services. This is because the overhead of VPN encryption results in a decrease of throughput and adds network latency.