APT tracks automatically installed, learn how you can use this feature to keep your Debian system as clean as possible, and how you can trim down your system without breaking it.
https://raphaelhertzog.com/2011/03/07/debian-cleanup-tip-6-remove-automatically-installed-packages/
This article explains what non-packaged files are, why they can be a source of problem, how you can identify them in order to clean your system.
If you're a tinkerer and hand-edit some files for some quick tests, or if you tend to re-install newer versions of some packages from the sources, you might have overwritten some packaged files a...
https://raphaelhertzog.com/2011/02/21/debian-cleanup-tip-4-find-broken-packages-and-reinstall-them/
Third-party packages can be very useful but can also become a maintenance burden over time. This article explains you how to identify them so that you can periodically go through the list and kee...
https://raphaelhertzog.com/2011/02/14/debian-cleanup-tip-3-get-rid-of-third-party-packages/
Lean what obsolete packages are, why you should remove them and how you can quickly get rid of them.
https://raphaelhertzog.com/2011/02/07/debian-cleanup-tip-2-get-rid-of-obsolete-packages/
Learn how to keep your Debian/Ubuntu system clean by removing old and unused configuration files from time to time.
https://raphaelhertzog.com/2011/01/31/debian-cleanup-tip-1-get-rid-of-useless-configuration-files/