PCLinuxOs is a fork from Mandrake Linux. In the past Mandrake and Connectiva were two different distros. In April 2005 Mandrake acquired Connectiva, meaning that developers took Mandrake as the base and made an independent distribution. This distro is designed primarily for the newcomers to Linux and comes with a hybrid CD. Meaning that you can either utilize the live CD as one without making changes to your system or continue with the installation. The distribution does not come with proprietary drivers and they can be installed after a hard disk install. Again a recommended download for new Linux users. Current release is 2009.2.
PuppyLinux despite it's cute name, is a very handy distribution especially for low end hardware. It has a small footprint, meaning that it does not use a big space with installation on your hard disk. As low as 93 MB are used. It can boot from a USB stick, CD or DVD media. This offers a faster computing experience, because of low system requirements. Like the other distributions the system is installed with office programs, browsers and image editors. Also with an additional software installation which has been made easy with Puppy software installer. We recommend this to users with older computers. We believe this is one of the distributions that will be beneficial for the users, since notebooks are becoming obsolete very quickly. Current release is 4.3, codenamed “Earth.”
CentOS (Community ENTerprise Operating System) is again one of the community distributions. This is mainly geared towards the organizations and individuals who need enterprise class computing, but can achieve operations without commercial support. The name of the distribution also comes from this idea, it is Community ENTerprise Operating System. It's based on the RedHat system and the developers goal is to update the CentOS repository within 72 hours of the new fix upload by RedHat. However users should be aware that there is absolutely no link between RedHat, Fedora Project and CentOS. The distribution is totally independent. Commercial support is a work in progress and has not been announced yet. There is no predetermined release cycle because CentOS is a remake of RedHat and follows their releases. Current release is 5.3.