When working with Red Hat, you should know about Red Hat's family.
Now, what is this family about?
Well, Red Hat participates in many open source projects.
It's true, they make money out of Red Hat Enterprise Linux,
but at the same time, people that are paid by Red Hat
are contributing to open source projects.
And one of these projects is Fedora.
It is a free community distribution that is sponsored by Red Hat.
And mature packages from Fedora are included in CentOS Stream.
CentOS Stream is the upstream project for RHEL,
where community developers can participate and contribute new software.
RHEL is derived from CentOS Stream
and offers an enterprise Linux distribution with support options.
Rocky Linux and AlmaLinux are derived from Red Hat Enterprise Linux
as free community alternatives.
There are other distributors that are derived from Red Hat as well,
like Oracle Linux and Amazon Linux, for instance.
But they are outside of the reach of Red Hat.
Let's talk about Fedora.
Fedora is a community project sponsored by Red Hat.
And the focus in Fedora is on the latest developments
and not so much on stability.
Fedora is a 12 to 18 month life cycle and no support options are available.
So you will have a new version of Fedora every six months normally.
Fedora is an awesome solution if you want to be ahead of the changes
and run Linux on modern hardware.
CentOS Stream is a different kind.
It's the upstream development platform for Red Hat Enterprise Linux.
And it includes software that has matured in Fedora.
And due to its ever-evolving nature,
CentOS Stream is not a recommended distribution to use in production environments.
Also, no support is available for CentOS Stream.
Red Hat Enterprise Linux is a supported Linux distribution
that is offered for use by organizations.
And it has a life cycle that spans up to a maximum of 10 years.
It offers support on the software
and it integrates in the Red Hat product family
where additional expertise, security, certification, and monitoring can be offered.
If you want to learn Red Hat,
it's good to know that unsupported free usage is offered
for up to 16 instances of Red Hat Enterprise Linux
using a developer account.
You can get that on developers.redhat.com.
I'll show you shortly.
Then there is Rocky Linux and Alma Linux.
Now, where should you see them?
Well, before 2019, CentOS was a free alternative to Red Hat Enterprise Linux
where all the Red Hat proprietary elements were removed.
Nowadays, CentOS Stream is the only version of CentOS
and it serves as the upstream to RHEL.
And Rocky Linux was created by the original founders of the CentOS project.
Alma Linux was created by Cloud Linux.
So these are independent products that are based on Red Hat Enterprise Linux.
Now, you might be tempted to use them,
but as Red Hat offers up to 16 instances of RHEL for free,
the need for free distributors like Alma and Rocky is not as big as it used to be.
And really, if you want to prepare for RHCSA, you should only use RHEL
because in RHEL, there's a couple of features that you won't find in Alma and Rocky.
And after all, the RHCSA exam is going to be based on RHEL.
In RHEL, there are different versions as well.
So it's a foundation for some other products like Red Hat CoreOS,
which is an image-based container host that is used in OpenShift environments,
or the Red Hat UBI, which is a universal base image,
which is a subset of RHEL packages that can be used as a foundation
for building custom container images.
And there is Red Hat Enterprise Linux AI and the RHEL inference server,
which both are tuned versions of RHEL used for hosting AI workloads.