The Yellowdog Updater, Modified (YUM) is an open-source command-line package-management utility for RPM-compatible Linux operating systems and has been released under the GNU General Public License. It was developed by Seth Vidal and a group of volunteer programmers. Though yum has a command-line interface, several other tools provide graphical user interfaces to yum functionality. As a full rewrite of its predecessor tool, Yellowdog Updater (YUP), yum evolved primarily in order to update and manage Red Hat Linux systems used at the Duke University department of Physics. Since then, it has been adopted by Red Hat Enterprise Linux, Fedora, CentOS, and many other RPM-based Linux distributions, including Yellow Dog Linux itself, where it has replaced the original YUP utility.  System administrators can automate software updates using yum-updatesd, the yum-updateonboot package, the yum-cron package, or PackageKit.

Display list of updated software

# yum list updates

Patch system by applying all updates

# yum update

List all installed packages

# yum list installed 

Check for an update to a specific package

# yum update {package-name} 

Install a specific package

# yum install {package-name} 

Remove a specific package

# yum remove {package-name} 

Display information on a specific package

# yum info {package-name} 

Clean all packages

# yum clean packages

Remove cached packages

# yum clean all

Read NTFS drives (Windows NT/2000/XP/2003) in Fedora

# yum install ntfs-3g

Display list of group software

# yum grouplist