Listing installed packages using dpkg
It took a long time using RedHat and Fedora distributions before I got proficient with RPM. Moving to Ubuntu requires learning an entirely new package management system, the Debian-based APT (Advanced Packaging Tool) and friends.
One of the more common operations using RPM is to query the packages installed on your system:
$ rpm -qa
It seems the same operation can be done using dpkg:
$ dpkg -l
You can supply dpkg with a pattern to limit the output to something less than all the installed packages. Also, of interest, if you want to see what files just got installed from an 'apt-get install
$ dpkg -L apache
This will list all the files with full pathnames for where they were installed.
Many thanks to the author of this article for some of the great tips: