Operating-system level virtualization on FreeBSD
Operating-system level virtualization is available in a few different ways on FreeBSD.
Jails have been a feature of since FreeBSD 4.X. Its a far more comprehensive solution compared to chroot. Whereas chroot only deals with the file system aspect of the operating system, jails are similar to running a sandboxed FreeBSD system, with its own processes, files, users and is nearly indistinguishable from the real OS.