Ubuntu Server reminds us of the Xenix, UnixWare, and even early SunOS and Solaris version that were targeted toward VARs and vertical market 'solutions' platforms. There are a lot of choices that arrive in the Ubuntu distribution, and it's based on Debian, which is known to be less experimental than other Linux distributions. It's fast, utilitarian, and among the first Linux distros to link to clouds and clusters using standard components. Ubuntu Server's not so much lightweight, as just a little loose and fast in places.