Dpkg

If you understand rpm or dpkg and want to learn the other

Issue	rpm	dpkg
how files are called	*.rpm	*.deb
list all installed packages	rpm -qa	dpkg -l
list all installed packages by order of installation date	rpm -qa --last
install a package from a file	rpm -i file.rpm	dpkg -i file.deb
list package content	rpm -ql package	dpkg -L package
find what package provides the installed file /bin/ls	rpm -qf /bin/ls	dpkg --search /bin/ls
look at a package file description		dpkg -I file.deb
look at a package description	rpm -qi package	apt-cache show package
find which installed package provides /bin/bash	rpm -qf /bin/bash	dpkg -S /bin/bash (to also search in not installed packages you can use apt-file)
find what program provides the file Xlib.h		auto-apt search Xlib.h
extract a package	rpm2cpio blah.rpm | cpio -id	dpkg -x datei.deb target_folder