BSD, unlike Linux, is not as fragmented with slightly different tasting flavours of the same thing. The main BSD variants have very different audiences and provide users with a fully functioning and integrated operating systems suited for specific workload duties. However, with on-going development, each BSD variant provides users with a general purpose operating system that can be deployed for a wider range of tasks.
Apart from ports that give end users the tools to set up their choice of BSD operating systems to perform a useful function, BSD bases are tightly integrated with the kernel, allowing for seamless operation, documentation and support. These base tools are not just a collection of singular tools that put together and called a distribution, these tools are tightly developed, with consistent switches or flags to make system management consistent and uniform.
Even though the different BSD distributions have different goals, their philosophies are similar, making it easy for system administrators to move between the maintenance of each, very easy with minimal learning.
You won’t find a better documented operating system or community that is there to help than BSD.
The main distributions are: