Centos vs Ububtu• The main difference is that CentOS is based on Redhat Enterprise Linux, while Ubuntu/Ubuntu Server has its roots in Debian.• One philosophical difference that no administrator on an Ubuntu system knows the root password (its randomly generated), and root-privileges are granted through the sudo command.• CentOS uses the YUM package manager with RPM packages, while Ubuntu uses apt with DEB packages.• Ubuntu tends to be less conservative than CentOS, which means that its repositories contain fresher packages, whereas CentOS packages are tend to focus on security patches only.
Ubuntu vs Debain• Ubuntu and Debian are closely related. Debian and Ubuntu are free Linux distributions using the apt package management system.• Ubuntu builds on the foundations of Debians architecture and infrastructure, but has a different community and release process.• Ubuntu and Debian are distinct but parallel and closely linked systems. The Ubuntu project seeks to complement the Debian project .• Ubuntu provides a system based on Debian with frequent, regular releases and a consistent desktop interface. It is backed by Canonicals commercial services and support on both the desktop and the server. It releases critical bug fixes and is never more than six months away from the latest version of anything in the open- source world.