FreeBSD is an amazing UNIX based operating system and the parent to MAC OSX. If you are using a MAC, you are using FreeBSD under the hood. This is an Operating System that has been around for awhile. It’s Built similar to how Microsoft Products are built in the sense that the core all comes from the same source. Linux, on the other hand, provides a kernel and there are several distributions that have been born to packages the other applications together which create an Operating System. Some of the Linux Distributions I have used and are fond of are CentOS (RedHat), SUSE Linux/OpenSUSE, and Ubuntu. Each has there advantages and disadvantages.
FreeBSD has come along way from its roots. Not only has FreeBSD provided the foundation for MAC OSX, it also provides the foundation for Juniper Networks JUNOS, and is the foundation for several appliances we use day to day. Both Linux and Android have made progress in the market, I have always found FreeBSD a comfortable system use. Heck if it was good for Steve Jobs and runs on iPad, iPhone, Mac, etc, then it deserves some credit.