I’m here to make it simple for you.

First things first: what is apt? Well, it stands for Advanced Packaging Tool (APT), which is basically the software management system in Ubuntu and other Linux distros. It helps us install new programs, update existing ones, and remove stuff we don’t need anymore. Pretty cool, right?

Now some of its commands:
– sudo apt install nmap (to install the network scanner)
– sudo apt remove nmap (to uninstall it)
– sudo apt update (to check for updates and download them)
– sudo apt upgrade (to actually apply those updates)

But what if we want to get fancy with our APT usage? That’s where the advanced configuration comes in. For example, you can add a repository (a collection of software packages) by running:

sudo echo “deb http://example.com/repo stable main” | sudo tee -a /etc/apt/sources.list

This will tell apt to look for packages from that specific repo when we run an update or upgrade command. Pretty neat, huh? And if you want to remove a repository, just replace “stable main” with “unstable non-free”, or whatever else you need to do.

Another cool feature is the ability to pin (or prioritize) certain packages over others. For example:

sudo echo “Package: nmap\nPin: release o=Ubuntu, a=stable, n=16.04, l=xenial/main\npin-priority: 990” | sudo tee -a /etc/apt/preferences

This will make sure that we always get the latest version of nmap from Ubuntu’s stable repository for Xenial (16.04), and give it a priority score of 990 (which is pretty high). If you want to remove this pin, just replace “990” with “-500”.

And that’s basically all there is to it! APT can be a bit overwhelming at first, but once you get the hang of it, it’s actually quite simple. Just remember: always use sudo when running apt commands (unless you want to accidentally delete something important), and don’t forget to update your system regularly.