YUM (Very Secure File Transfer Protocol Daemon )
YUM stands for Yellow dog Updater, Modified because it is based on YUP, the Yellow dog Updater. Yellow Dog is a version of Linux for the Power Architecture hardware. YUP, and later YUM, were written by the Linux community as a way to maintain an RPM-based system.
Advantages of YUM
Automatic resolution of software dependencies. If a package installation or upgrade request is made and requires the installation or upgrade of additional packages, YUM can list these dependencies and prompt the user to install or upgrade them.
Command-line and graphical versions. The command-line version can be run on a system with a minimal number of software packages. The graphical versions offer ease-of-use and a user-friendly graphical interface to software management.
Multiple software locations at one time. YUM can be configured to look for software packages in more than one location at a time.
Ability to specify particular software versions or architectures. Software locations accessible by YUM can contain multiple versions of the same RPM package and different builds for different architectures such as one for i686 and one for x86_64. yum can easily check the appropriate version and download it.
While it's unlikely that you'll have an Internet connection during the exam, you could have a network connection to a local repository. So you should be ready to use the yum command during the Red Hat exam.