FreeBSD is a complete OS, while debian is a distro, i.e the Linux kernel + a lot of programs including the utilities from GNU. So almost everything in debian comes from a package while in the BSD world, there's a split between the system utilities (called base) and the third-party projects (called ports). The port system itself is a collection of recipes to build those projects.

But the nicest thing about the software in the base is that they are developed in sync with the OS, so their code can be simpler.