Before we can talk about ubuntu, we need to talk about Debian and the Debian family and the Debian.
It's a project, it's a community driven project and there's not a dominant commercial entity driving
this project.
Another philosophy of the Debian team or this community is that their philosophy is it's ready when
it's ready.
So the goal here is to ensure high quality releases and not really to adhere to a strict time plan or
release roadmap.
So it can be that for example, the next large Debian stable release might get delayed if something
isn't ready yet.
It uses the dpkg and apt for package management.
So dpkg is responsible for installing the individual packages and apt allows us to have a front end
in order to allow us to easily update our system or to install software.
And there are many distributions derived from it.
So the Debian core, it serves as a base for many other distributions, including Ubuntu and many other
derivatives.
It's also quite a universal operating system that means that it's suitable for various applications
from desktops to servers.
There are different branches of Debian and one would be the experimental branch and this offers you
highly or highly unstable packages and concepts and this is used for early testing.
So new features first are implemented into Debian experimental and this allows users to test those.
I would recommend you to not use this unless you really want to run into bugs and into problems.
The next branch is unstable sometimes also called Debian.
Sid and this is the active development branch with the latest software.
It's more stable than experimental but it's still not stable.
So this is not recommended for critical use.
When I was, for example going to high school I was using Debian Sid on my machine, but every now and
then it would break after an update and I had to figure out how to fix it.
It taught me a lot about Linux, but if you're relying on your system for your job then I would say
this is still a little bit too unstable.
Then we got testing.
Those are pre-release packages bound for the next stable version of Debian and they are more updated
but they still might have minor bugs.
So I would also recommend you to not use this one.
And then we have stable Debian.
This is production ready thoroughly tested and usually it's older but therefore more reliable software.
So this is something that you might want to use on a server.
As you can see there are different branches here and changes do need to make their way through until
they are eventually then in stable, stable then means it's really stable.
But it also means you might not get the latest software there.
Let's just have a look at Debian.
Usually when we just talk about Debian we are referring to Debian stable though.
Be aware there are those other branches.
They are also more branches that I haven't listed on the slide.
I've only listed the four most important ones we can see here.
This is a Linux system here.
Right now it's version 12 here.
It might be another version that's installed for you.
It doesn't really matter.
I just want to highlight a few differences.
We can see that it looks slightly different than Ubuntu.
There's no sidebar here with icons.
Um, another thing that we might want to test would be, for example, an apt update whether this one
here still works exactly the same.
And if we are now here executing this we can see it's connecting and it's working here right now.
The release is called Bookworm and it has updated all of those.
Now I could do an apt dist upgrade to just upgrade my whole system.
And as you can see here, it works pretty much as we have seen it on Ubuntu.
It's now trying to update here quite a bit, but this one here looks quite good.
I've uh, I've decided now not to update the system because it's just a virtual machine and I will throw
or I will delete it just after recording this.
Anyway, the next changes that I would like to highlight is that pretty much all a lot of things are
shared with Ubuntu, but a few things are differently.
So for example, if I would go into my Etsy apt folder there we could see that we got our sources.list
file here and if I now want to edit this we will see that our repositories are different.
Those are the websites from where our packages will be downloaded and we can see there's nothing here
with ubuntu.
So the syntax here is still exactly the same as we have seen it on our ubuntu.
But we can see here all of this is different.
This is our Debian release and then we have different branches for our um for our um.
Like certain packages are in the main branch.
Um and others are in other branches there.
Those branches are not really Debian branches, they are more like branches from our package management
or channels that we want to subscribe to.
Here we are subscribing to the main channel of the bookworm release of Debian stable.
They all have names so if you run this it will probably be here a different name, but we can see this
is slightly different here than for example on an ubuntu.
By the way, please really do not add ubuntu repositories into the Debian sources.list.
It might work at first, but then at some point you might run into serious problems or dependency issues
there.
So really avoid that and only add repositories into this sources.list or sources.list d folder.
Um when they're really made for Debian and not ubuntu.
But aside from that, it will be extremely similar.
So you've seen how we can update our system.
And of course a lot of other things are still the same.
Systemctl status here will work.
So it's not like we need to learn everything from scratch.
It's more like if you've worked with Ubuntu before, this will be this will feel extremely similar.
So one thing that I for example like to do, I do have lots of experience with ubuntu and then if I
run a server i can just use a Debian stable there and it will feel almost the same.
And this can be a way to approach this.
This might be, for example a great operating system for a server, but the Debian family is bigger
because again Debian is open source software.
So all of the code is released under the GPL license.
I mean it's released before, but then the Debian team or the community takes the source code and does
some adjustments there.
And then those adjustments are shared as well under the GPL license as open source software as required
by the license.
And this means that there can be additional Linux distributions that take the source code of Debian,
make more changes to them then and then release their own um distribution there.
And some of those would for example be Ubuntu or Kali Linux for security and security optimized Linux
in the sense that we can do for example white hat hacking with Kali Linux and it comes with all the
tools that we need for that or an operating system optimized for running on a Raspberry Pi or certain
versions of Linux.
Mint might also directly build on top of Debian, though some others of Linux might build on top of
Ubuntu, but Ubuntu then builds also on top of Debian.
So this is like a whole family here.
And as you can see there's not just Debian, but there are also those derivatives or distributions that
build on top of that and one really popular one that we have also worked with here in this course would
be Ubuntu.
And this is what we will have a more in-depth look at in the next lecture.