Editing Linux Basics Tutorial (section)

== Using the Package Manager (apt/apt-get) ==

One of the most useful functions of Linux is the use of package managers. This is a way of installing software that is very different than in Windows. The idea is to automate the updating of software and the management of software dependencies. So, if you want, you could theoretically update all the software on your machine at once.

This is done through keeping track of all the software, or "packages", installed on your machine. So, installing software is done through the package manager. Then, you can run a single update function, and the package manager will go through and update everything it's keeping track of.

The package manager used in Ubuntu is called "apt" (formerly called "apt-get" - the usage is entirely the same; apt just looks nicer). Following are some useful commands that use apt:

'''NOTE''': apt requires that it is run as root, so all of these commands should have "sudo" before them.

* '''apt install''': Installs the package given as an argument.

* '''apt remove''': Uninstalls the package given as an argument. Does not uninstall dependencies for that package, in case other packages need it.

* '''apt update''': Downloads information on what upgrades are available for packages. Does not actually perform those updates.

* '''apt upgrade''': Updates all software that it has new updates for. You'll typically want to run <code>$ sudo apt update</code> before this so that you'll have the most up-to-date updates.

* '''apt autoremove''': Uninstalls all dependencies that are no longer needed for packages you've installed. For example, if package x depends on package y, and you remove package x, you can use <code>$ sudo apt autoremove</code> to remove package y.

* '''add-apt-repository''': Adds a new location to look for package information. apt comes with a preinstalled set of standard repositories, but to extend the amount of software you can install, you'll need to add new repositories.

Typically, if you want to install something from online (and it's available for Linux), it will have code snippets you can run to use apt to install it.