Most of Debian and/or it’s derivatives uses apt-get to find the packages they wanted to install on their system. This is working as Debian has a very large repositories which contains lots of packages. The same goes with some other big distribution like Mandriva and OpenSUSE. What about Slackware?
Slackware do not have official repositories outside slackware.com (and slackware.osuosl.org for now) which is maintained by Patrick himself. There are however other repositories which contains SlackBuild Script and/or Slackware packages, like LinuxPackages, Slacky.EU and SlackBuilds project.
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