If you have ever gotten a bit lost trying to tell Fedora, RHEL, CentOS, Rocky and AlmaLinux apart, you are in good company. They are close cousins, they share a huge amount of code, and yet each one sits in a very specific spot. The good news: once you see how the family fits together, it clicks. And to really see it, you have to go back to the nineties and to one December in 2020 that changed everything.
From Red Hat Linux to the great split of 2003
In the early nineties, Marc Ewing created a distribution called Red Hat Linux. Bob Young soon joined him, and together they founded Red Hat, Inc., which went on to become one of the most influential companies in free software. That original Red Hat Linux had a long run and reached version 9, released in 2003.
That same year, Red Hat made a strategic call that still shapes the field today: it split the project into two paths. On one side came Fedora, a community-driven, free distribution with fast-moving innovation, designed as a lab where the newest technologies get tested. On the other came RHEL, Red Hat Enterprise Linux, the paid commercial product aimed at businesses, with long-term support and rock-solid stability.
The logic is neat. Fedora moves fast and experiments, RHEL takes whatever is already mature and ships it with guarantees. Fedora is the upstream, the source the enterprise product draws from.
CentOS: the free clone that conquered servers
The snag with RHEL is that it costs money. And plenty of people wanted that same solid base without paying the subscription. Enter CentOS in 2004: a free, binary-compatible clone of RHEL. In practice it was RHEL without the branding, without official support and at no cost. For universities, small businesses, hosting providers and hobbyists it was a gift, and it spread across millions of servers.
CentOS became so important that in 2014 Red Hat decided to acquire the project outright and bring it into its orbit. Five years later, in 2019, IBM bought Red Hat for around 34 billion dollars, one of the largest software deals in history. All the pieces were in place for the earthquake.
The December 2020 earthquake
On December 8, 2020, Red Hat announced a turn that shook the whole community: CentOS would stop being a stable clone trailing behind RHEL and become CentOS Stream instead, a development branch sitting ahead of RHEL. So rather than following the enterprise product, it would now lead it.
The change had huge implications. Traditional CentOS, that faithful replica of RHEL so many people ran in production, was suddenly on borrowed time with an earlier end-of-life date. Plenty of users felt betrayed. They had built entire infrastructures on the promise of a free, stable clone, and that promise was vanishing.
The new family flow looked like this:
- Fedora: community upstream, cutting-edge innovation.
- CentOS Stream: the branch where the next RHEL release is cooked up.
- RHEL: the stable, paid enterprise product with long support.
- 1:1 clones: free replicas that rebuild RHEL from its source.
Rocky Linux and AlmaLinux: rising from the ashes
The community’s reaction was swift and, frankly, spectacular. Gregory Kurtzer, one of the original co-founders of CentOS, announced just days later that he would start a new project to recover the spirit of classic CentOS. That is how Rocky Linux was born, named in memory of Rocky McGaugh, another early CentOS contributor. Its first stable release arrived on June 21, 2021.
Almost in parallel, the company CloudLinux backed its own alternative: AlmaLinux, whose first stable version shipped on March 30, 2021, actually beating Rocky to it. Both chase the same goal: a free, stable, 1:1 binary-compatible clone of RHEL, filling exactly the gap left by good old CentOS.
Today, anyone after that enterprise base without paying has two solid successors to pick from, while CentOS Stream carries on as RHEL’s testing ground.
How to choose within the family
The decision comes down to what you need it for:
- If you love the newest things and do not mind frequent updates, Fedora is your home.
- If your company needs official support and certifications, RHEL is the paid option.
- If you want RHEL stability for free on your servers, look at Rocky Linux or AlmaLinux.
- If you develop software that will run on RHEL and want to test it early, CentOS Stream makes sense.
The Red Hat family is a perfect example of how free software lets the community carry on even when a company changes course. Where some saw the end of CentOS, others built two brand-new projects that keep that ideal alive today. And all of it grows from the same great tree that started with a Red Hat Linux back in the nineties.
Sources: Wikipedia: Rocky Linux, Wikipedia: Red Hat, IBM: acquires Red Hat.
