CentOS was a Linux distribution based on Red Hat Enterprise Linux, itself being based on Fedora, which is being based on the discontinued Red Hat Linux. It intended to be a fully compatible, free and community supported counterpart of RHEL, with CentOS releases tracking RHEL releases. The distribution in its original form was developed from 2004 to 2020, when it was replaced by CentOS Stream. Similarly to Fedora and RHEL, it uses the YUM package manager and Anaconda installer. By default, it uses GNOME when the GUI option is enabled during setup, although other environments are also available from the repositories.

The latest version, CentOS 8, was released in 2019 and was based on Red Hat Enterprise Linux 8.