Debian Package Management
debian 9 The Debian Administrator’s Handbook
debian.org/doc Debian Documentation
wiki.debian.org DebianPackageManagement
Debian package management consists of several layers. The lowest layers are made up of dpkg and associated programs. On top of these layers is the Apt family of tools such as apt, apt-get, apt-cache, and others. See the Package Management Tools page for a description of other tools for working with DebianPackage files.
wiki.debian.org DebianPackageManagement#Apt
wiki.debian.org Apt
reddit.com/r/debian Has the Aptitude development been abandoned?
Good discussion on package management tools.
reddit.com/r/debian Can someone explain apt-get vs apt vs aptitude to me?
The Debian GNU/Linux FAQ - Chapter 8 - The Debian package management tools
Remove a package (but not its configuration files): dpkg –remove foo.
Remove a package (including its configuration files): dpkg –purge foo.
For instance, use this PPA repo
use ubuntu ppa repo on debian
sudo add-apt-repository ppa:openscad/releases