redhat.com
Red Hat is the world's leading open source technology solutions provider with offerings including Red Hat Enterprise Linux, open source applications, security and systems management, virtualization, Services Oriented Architecture (SOA) solutions.
Linux时代
Linux时代是中国最大的Linux应用与开发人员的专业社区，栏目包含Linux新手，Linux安装，Linux管理员，Linux开发者，Linux桌面，Linux编程，Linux数据库，Linux网络技术，Redhat，Fedora，Ubuntu，SuSE，Unix，debian。
ChinaUnix
ChinaUnix是中国最大的Linux/Unix技术社区网站，我们还交流程序开发，数据库，存储备份，服务器技术，网络安全等技术，并提供IT人才招聘，软件下载，BLOG，IT培训等服务。
Ubuntu
Super-fast and great-looking, Ubuntu is a secure, intuitive operating system that powers desktops, servers, netbooks and laptops. Ubuntu is, and always will be, absolutely free.
openSUSE
openSUSEopenSUSE 是一个自由的、基于Linux的操作系统，适用于您的个人电脑、笔记本电脑或服务器。您可以畅游网络、管理您的电子邮件与照片、办公、欣赏视频与音乐。
Debian
Debian GNU/Linux is a free distribution of the GNU/Linux operating system. It is maintained and updated through the work of many userswho volunteer their time and effort.