diff --git a/knowledge base/dnf.md b/knowledge base/dnf.md
index 5ff8b60..82b007b 100644
--- a/knowledge base/dnf.md	
+++ b/knowledge base/dnf.md	
@@ -168,6 +168,8 @@ Not to mention,
 - [How to install only security and bugfixes updates with DNF]
 - [How to use YUM/DNF to downgrade or rollback some package updates?]
 - [How to lock kernel (or another package) on Fedora]
+- [Appendix A. DNF commands list]
+- [A quick guide to DNF for yum users]
 
 <!--
   Reference
@@ -178,11 +180,13 @@ Not to mention,
 [yum]: yum.md
 
 <!-- Upstream -->
+[appendix a. dnf commands list]: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/9/html/managing_software_with_the_dnf_tool/assembly_yum-commands-list_managing-software-with-the-dnf-tool
 [dnf command reference]: https://dnf.readthedocs.io/en/latest/command_ref.html
 [dnf configuration reference]: https://dnf.readthedocs.io/en/latest/conf_ref.html
 [using the dnf software package manager]: https://docs.fedoraproject.org/en-US/quick-docs/dnf/
 
 <!-- Others -->
+[a quick guide to dnf for yum users]: https://opensource.com/article/18/8/guide-yum-dnf
 [cheat.sh]: https://cheat.sh/dnf
 [how to install only security and bugfixes updates with dnf]: https://fedoramagazine.org/how-to-install-only-security-and-bugfixes-updates-with-dnf/
 [how to lock kernel (or another package) on fedora]: https://robbinespu.gitlab.io/posts/locking-package-fedora/
diff --git a/knowledge base/yum.md b/knowledge base/yum.md
index 0d78edf..949cc71 100644
--- a/knowledge base/yum.md	
+++ b/knowledge base/yum.md	
@@ -1,7 +1,7 @@
-# Yellowdog Updater Modified
+# Yellowdog Updater, Modified
 
 Command-line utility for RPM used by Red Hat Linux and derivates.<br/>
-Replaced by [DNF] in Fedora.
+Replaced by [DNF] in Fedora 22+ and RHEL 8+.
 
 1. [TL;DR](#tldr)
 1. [Further readings](#further-readings)
@@ -18,26 +18,70 @@ YUM.
   <summary>Usage</summary>
 
 ```sh
-# Check for updates.
-sudo yum check-update
+# Get help.
+yum help
+yum help localinstall
 
-# List available packages.
-sudo yum --showduplicates list available 'gitlab-ee'
+# Refresh the repositories' metadata.
+yum makecache
+
+# Check for updates.
+yum check-update
+
+# List packages.
+yum --showduplicates list available 'gitlab-ee'
 
 # Display information about packages.
-sudo yum info 'gitlab-ee'
+yum info 'gitlab-ee'
 
 # Install packages.
-sudo yum install 'buildah' 'jq-0.5.6-1.fc24'
-sudo yum -y install 'Downloads/tito-0.6.2-1.fc22.noarch.rpm' --setopt='install_weak_deps=False'
-sudo yum install 'https://kojipkgs.fedoraproject.org/packages/tito/0.6.0/1.fc22/noarch/tito-0.6.0-1.fc22.noarch.rpm'
+yum install 'buildah' 'jq-0.5.6-1.fc24'
+yum -y install 'Downloads/tito-0.6.2-1.fc22.noarch.rpm' --setopt='install_weak_deps=False'
+yum install 'https://kojipkgs.fedoraproject.org/packages/tito/0.6.0/1.fc22/noarch/tito-0.6.0-1.fc22.noarch.rpm'
 
 # Upgrade packages.
-sudo yum update 'gitlab-ee-16.11.3'
+yum upgrade 'gitlab-ee-16.11.3'
+yum --obsoletes --best update
 
 # Clear the cache.
-sudo yum clean packages
-sudo yum clean all
+yum clean packages
+yum clean all
+
+# Show enabled repositories.
+yum repolist
+
+# Display information about enabled repositories.
+yum repoinfo
+yum repoinfo 'kernel-livepatch'
+
+# TODO
+yum alias
+yum autoremove
+yum check
+yum repoquery --deplist
+yum distro-sync
+yum downgrade
+yum group | yum group summary
+yum group info
+yum group install
+yum group list
+yum group mark
+yum group remove
+yum group upgrade
+yum localinstall
+yum history
+yum list
+yum mark
+yum module
+yum provides
+yum reinstall
+yum remove
+yum repository-packages
+yum search
+yum shell
+yum swap
+yum updateinfo
+yum upgrade-minimal
 ```
 
 </details>