Upgrade installed packages to the newest available versions

Package management utility for RHEL, Fedora, and CentOS (replaces yum).
More information: <https://dnf.readthedocs.io>.
Trick copyright: tl;dr; <https://github.com/tldr-pages/tldr>

sudo dnf upgrade

click the source code to copy install dnf on any operating system with command-not-found.com