Before we install Ros2, it's important to check which ros2 distribution you need to use, and you can
find a list of all distributions on the official documentation here.
So just in case you can type Ros two distributions on Google or any web browser, and you will find
this distribution page here.
Okay so that's quite easy to find.
So here we have a list of all available ros2 distributions in green.
You have those who are currently supported and in gray or white those who are not supported anymore.
As you can see here, a new distribution is going to be released every year on May 23rd.
Okay, so before it was not the case, but since 2021 you can see May 23rd for each new distribution.
And it's quite easy to know what's the order of the distributions because it simply follows the alphabetical
order.
You can see the first version here after the alpha and beta was added.
So that's a and then b, c d e f.
And now we have for example j with jazzy.
And so from this you know that the next one is going to start with a k and then L etc. also, you can
see for each distribution we have two names.
Okay, but we only really use the first one.
So here for example we're going to name that distribution here Ross two Jesse.
And one of the most important thing to check for a distribution is the EOL date.
And EOL means end of life.
After this date, the distribution will not be supported anymore.
So after that you should preferably not use it.
It doesn't mean it's not going to work, it's just that you won't get any new updates and after the
EOL date.
The second important thing to check is is this distribution an LTS version or not?
LTS means long term support.
So every year you have a new distribution.
All right.
But it alternates between an LTS and a Non-lts version.
An LTS version is going to be supported for five years and can be considered more stable.
You can see, for example, with Ros2 humble.
That was the first LTS version supported for five years with Ros2.
So you can see May 2022 until May 2027.
We also have jazzy 2024 until 2029, and Non-lts versions are going to be supported for only one year
and a half.
As you can see here with Aaron, we have May 2023 until November 2024.
So knowing all that which version to use.
Well, what I do and what I recommend you to do is to use the latest LTS version, provided that its
been released at least for a few months, so it's more stable and contains all the core packages you
need in this case.
For this course we will choose Ros two jazzy.
That will be perfectly fine to start your learning journey, and then when you start to have a few Ros
two projects and a new LTS version is released, then I advise you to well, test this version and see
if everything is working.
But sometimes not everything is going to be available at the beginning, so you may have to wait a few
months.
It depends.
But let's say 3 to 6 months before you port your code to the new Ros two LTS distribution.
Also, I don't recommend working with non-lts versions like Galactic Ion, etc. those are just released
so you can get the latest tools and features.
So it's nice to test stuff, but it may be less stable.
And also all Non-lts versions are only supported for one year and a half.
So if you are learning, if you want stability, or if you want to use Ros2 for an actual real product,
then I advise you to only stick with LTS versions.
And one last thing that is important to pay attention to, and that's going to be helpful for.
The next lesson in this section is which OS version you need for the Ros2 version that you choose.
So let's click on jazzy here for example, and supported platforms.
So in this course we will focus on ubuntu.
That's what I'm going to look at.
And as you can see with Ros2 jazzy, we need to install ubuntu 24.04 for a different ros2 version.
For example, if I go back and I go to humble, which was an older LTS version, you see that it was
ubuntu 22.
Okay, so when you use a different ros2 version, you also have to use a different ubuntu version.