CentOS 5.6 is the fifth update to the CentOS 5 distribution series. It contains a lot of bugfixes, updates and new functionality. It is created by compiling the source packages for Red Hat Enterprise Linux. CentOS 5.6 is based on the upstream release 5.6 and includes packages from all variants including Server and Client. All upstream repositories have been combined into one, to make it easier for end users to work with.
About CentOS
CentOS is an Enterprise-class Linux Distribution derived from sources freely provided to the public by our Upstream OS Provider (UOP). CentOS as a group is a community of open source contributors and users. Typical CentOS users are organisations and individuals that do not need strong commercial support in order to achieve successful operation. CentOS is 100% compatible rebuild of the Red Hat Enterprise Linux, in full compliance with Red Hat's redistribution requirements. CentOS is for people who need an enterprise class operating system stability without the cost of certification and support.