Ubuntu is based on Debian; it's designed to be more user friendly, easier to use; but it's also less "pure" in the way it handles non-oss packages. Fedora is Re

Ubuntu is based on Debian; it's designed to be more user friendly, easier to use; but it's also less "pure" in the way it handles non-oss packages. Fedora is RedHat-based and it's the community-supported, bleeding edge version of RedHat/CentOS. If you're looking for a desktop OS, Fedora and Ubuntu will do well. I haven't played around with Arch.