When I was a beginner in Linux and I wanted to install any software, the online instructions I found would ask me to type something like this on my Ubuntu’s terminal
sudo apt install <software name>
or sometimes like this
sudo apt-get install <software name>
So I used to wonder what are these apt and apt-get commands. In this article, I am trying to explain the need for these commands and what they do internally to install software and how they do it.
What is apt? apt stands for “Advanced Packaging Tool”. It is a package manager that is used for managing the installation, updating, and removal of software packages in a Debian based Linux system.
That’s the short version of the answer, but don’t worry if you don’t understand it completely as this article is all about breaking down the above answer into parts and learning it in detail!
Let’s take this short answer and highlight the important terms that we need to understand.
It is a package manager that is used for managing the installation, updating and removal of software packages in a Debian Based Linux System.
If you look at the above 2 lines from a beginner’s perspective a lot of questions come into mind. Some of these are
- What are these software packages?
- What is a package manager?
- What are the functions of a package manager?
- Why only Debian based system?
- What are other alternatives for apt that I can use on my Debian based system?
Let’s try to learn the answer to all these questions in detail in this article.
I have already written another article explaining all about packages and package managers in detail that you can find in the link below.
In that article, I have explained
- What are packages in a Linux system
- Content of packages
- Need for package managers
- Functions of package managers and
- the architecture of packages managers
If you haven’t already, please go ahead and read that one before continuing this article as that article should clear up most of the confusion that is common with beginners who would like to learn more about “apt” commands.
Alright, I guess by now, you have read that article and you are more familiar with the role of package manager like “dpkg” (which stands for Debian package manager) in our Ubuntu Linux systems. Let’s next talk about apt and apt-get.
Why there are 2 of these commands? apt and apt-get?
Both these commands are just different methods of invoking our package manager dpkg. The “apt-get” command is the older of these 2 and “apt” is just a refreshed version with more focus on making things simpler for the end-user. You can use both to do the same thing in most cases
For example, if you want to install Firefox on your system, you can either enter the command
sudo apt install firefox
sudo apt-get install firefox
But as we saw the “apt” command is meant to be short, simple and focussed on the end-user’s experience. An example is the addition of the progress bar while we install packages on the command line as shown in the screenshot below.
Let’s take a look at a comparison of apt and apt-get.
|Newer version command to act as a front-end for APT||Older version command to act as a front end for APT|
|Has progress bar||No progress bar|
|Has limited functionality||Has more functionality, and it’s used with bash-scripts more than apt because of guaranteed backward compatibility|
Next, let’s have a look at the comparison of apt and apt-get commands
|apt install <software name>||apt-get install <software name>||Installs a software|
|apt remove <software name>||apt-get remove <software name>||Removes software but keeps configuration (user settings) files|
|apt purge <software name>||apt-get purge <software name>||Removes and deletes configuration files|
|apt update||apt-get update||updates packages list|
|apt upgrade||apt-get upgrade||upgrades software to their latest versions|
|apt full-upgrade||apt-get dist-upgrade||upgrades packages and removes old unnecessary ones|
|apt autoremove||apt-get autoremove||removes unnecessary dependencies|
|apt search <keyword>||apt-cache search||searches packages based on keyword|
|apt show||apt-cache showpkg||shows information about a package like version, dependencies, etc,.|
|apt list||–||lists packages based on certain criteria|
|apt edit-sources||–||edits sources.list file with some sanity checks|
Other than the ones listed above, the “apt-get” family of commands has more commands that have no substitute yet in the “apt” family. Some examples include
apt-get build-dep apt-get check apt-get download apt-get changelog apt-get clean apt-get autoclean apt-get changelog apt-get indextargets
man apt-get man apt-cache
to get a list of options supported by apt-get and apt-cache
I leave it unto you to read the man pages and try out these commands for yourself and play with them!
When to use apt and when to use apt-get?
It is recommended to use apt commands on the terminal and apt-get on the bash scripts.
This is because “apt” being the newer version is constantly evolving and can sometimes break backward compatibility. For example, the commands that worked in version 1.7 of apt may or may not work in 2.0.
If we were to use apt on our scripts then we need to go into the script files and edit them again version after version till its finalized. For this reason, the “apt-get” family of commands is preferred over “apt” as they have guaranteed backward compatibility.
Also apt-get family has more functionality for usage in scripts that will give the programmer more control over the required outcome.
Isn’t “apt” a short form for “aptitude”?
Yes and No!
The word “aptitude” in English means “a natural ability to do something.’ and apt as we saw stands for Advanced Packaging Tool.
But Linux developers have developed another tool named “aptitude” (named it that way just for fun since most people tend to think apt stands for aptitude as both these words kinda sound similar!). This tool provides a simple GUI inside the command line for easy management of packages. You can invoke this program using the command
and this will take you to a GUI that looks like this
I leave it to you to play around and explore the options it provides!
What does “Debian based system” mean?
There are 2 types of Linux distros
- Original distributions
- Derived distributions
Making a Linux distro from zero involves a lot of work to put all the packages and the Linux kernel together into a single “distributable” Operating system.
Original distributions are those that are made this way from zero. In other words, these original ones take the kernel, GNU utilities, application software, etc. and combine them into an installable operating system and distribute them to the end-users usually over the internet. Popular examples of original distros include Debian, RedHat, Slackware, etc.
Derived distros are ones that take one of these original distributions, make some changes to it, so that its more suitable for a specific purpose and then distribute them as an installable operating system.
Debian is the original distro here that used “apt” and “apt-get” and all the distros derived from it also use the same package management system as their defaults. Some examples of Debian derived distros include the Ubuntu family (Ubuntu, Lubuntu, Kubuntu, etc), Linux Mint, Kali Linux and PureOS. You can read more about these derivatives over at Debian.org in this link.
Will “apt” only work on Debian based system?
No, you can use the “apt” tool on other systems too. But like I explained in this article apt can only work with dpkg package manager that works with packages in the .deb format. So the packages you that we are trying to install or remove or update must be in the .deb format!
For example, you can’t open an excel “.csv” document using Microsoft word and expect it to work just fine. Similarly apt tool can only work with .deb files!
You can still use apt on Red Hat based distros or other Linux distros using tools like “alien” which converts between .deb and .rpm package formats, but the hassle to make everything work is not worth the effort, as conversions will bring their own set of problems in some circumstances.
So my advice is to stick to the default package managers that come with the Distros and learn their commands instead of trying to fit a square peg into a round hole!
And with that, I will conclude this article!
I hope you guys enjoyed this article and learned something useful.
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