YUM (Yellowdog Updater Modified) is an open-source, widely used command-line and graphical-based package management tool for RPM (RedHat Package Manager) based Linux systems, including, but not limited to, Red Hat Enterprise Linux (RHEL), CentOS, Scientific Linux (SL), Oracle Linux (OL), Rocky Linux and AlmaLinux, which is used to install, update, remove or search software packages on a system.