Linux software package types
As you've already learned by now, a Linux distribution comes packed with a Kernel and applications on top of it. Although plenty of applications are already installed by default, there will certainly be occasions when you will need to install some new ones or to remove ones that you don't need.
In Linux, applications come bundled into repositories. A repository is a centrally managed location that consists of software packages maintained by developers. Those packages could contain individual applications or operating system-related files. Each Linux distribution comes with several official repositories, but on top of those, you can add some new ones. The way to add them is specific to each distribution, and we will get into more details soon.
Linux has several types of packages, but as we are only covering Ubuntu and CentOS, we will mostly refer to the ones those two distributions use. Ubuntu uses
deb packages, as it is based on Debian,...