Yellowdog Updater, Modified, one of the last remaining vestiges of Yellow Dog Linux, is the package manager used by Red Hat, Fedora, and CentOS systems and their derivatives. It can handle the installation and removal of software packaged as rpms for these Linux distributions. Below are some simple examples of use:
search
This command will attempt to locate software packages in the configured software repositories that match the given search criteria, and display the name / version / repository location of the matches it finds. To use it, enter the following command:
yum search <queryString>
install
This command will attempt to locate and install the named software from the configured software repositories, recursively locating and installing any needed prerequisite software as well. To use it, enter the following command:
sudo yum install <packageName>
update
This option is used to install the newest versions of all packages currently installed on the system. Packages currently installed with new versions available are retrieved and upgraded; new prerequisites are also retrieved and installed as necessary, and replaced or obsoleted packages are removed. To upgrade, enter the following command:
sudo yum update
Unlike apt, most yum commands will also automatically check for updates to repository metadata if a check has not been done recently (or if forced to do so) and will retrieve and scan updated metadata so that information about new and updated packages is available before the requested operation is performed.