Chances are, your computer came with Windows or macOS. These operating systems may seem free, but they're not. Manufacturers have to pay Microsoft for Windows, and macOS updates are only available to people who have purchased Macs. On our end, the cost is hidden in the price of the computer.

There are many operating systems that are actually free. The most popular is Linux, but keep reading. By the time you finish this list, Linux will seem downright mainstream. Here are ten weird or obscure operating systems that most of us have never heard of.

1. FreeBSD

If you're using a free operating system that isn't Linux, then it's probably based on BSD. FreeBSD is only one of several UNIX-like operating systems. Others include NetBSD, OpenBSD, and PC-BSD. Whichever one you use, much of the experience is similar to what you will find on Linux. Free and open source software available for one is typically able to run on the other.

Even if you're not a free software lover, you may be using parts of FreeBSD without realizing it. Due to the project's permissive license, some of the code has made its way into Apple macOS, the Sony PlayStation 4, and Juniper routers.

2. ReactOS

Most free operating systems provide an alternative to Windows. ReactOS, in a sense, strives to be Windows. The goal is giving users a means to run software made for Windows without having to buy an operating system from Microsoft.

ReactOS is a free and open source operating system, so it can't utilize any of Windows' actual code. The project has partially implemented many Windows APIs, and it collaborates with the Wine project to get programs up and running.

3. FreeDOS

Do you live in the terminal? Did you use computers back when that was the only option? Are you having fond memories of MS-DOS?

FreeDOS lets you relive that bygone era. The barebones OS gives you a means to run old DOS programs on more modern hardware or inside a virtual machine. Or you can just use it to run old games.

4. Haiku

Image Credit: Haiku

Haiku draws inspiration from BeOS. Drawing a blank? Me too. BeOS was a graphical operating system developed by Be Inc to run on the BeBox back in 1995. The operating system stuck around for five years, before the last update went out in 2000.

BeOS may not have been a household name, but it picked up some users, and a few wanted to see the OS live on enough to create their own open source version. The goal is for software written for BeOS to work on Haiku, sort of like what ReactOS wants to do with Windows. All things considered, the Haiku team probably has an easier job on its hands.

5. illumos

Oracle used to maintain an operating system called Solaris. It was originally closed source, but the project became open in 2008. Oracle discontinued OpenSolaris in 2010 and went back to a proprietary model with Solaris 11 in 2011.

illumos is an effort to keep OpenSolaris alive. Like Linux, you don't download illumos directly. Instead, you grab a distribution such as DilOS or openindiana.

6. Syllable [Broken URL Removed]

Syllable desktop
Image Credit: Wikimedia

Syllable is based on AtheOS, an AmigaOS clone that was abandoned around the turn of the century. As for AmigaOS, it's still alive despite being born in the 80s for a line of computers long considered ancient.

Syllable targets home and home office users with a usable interface and native apps, including a Webkit-based web browser and an email client. Thing is, it can do this on a computer with only 32MB of RAM (though at least 64MB is recommended for browsing). The full installation should only take up around 250MB of hard drive space.

7. AROS Research Operating System

While Syllable is based on an AmigaOS clone, AROS takes a different approach. It actually aims to be binary compatible with AmigaOS at the API level. This is similar to how ReactOS targets Windows, and Haiku targets BeOS.

You may be wondering if it's worth giving AmigaOS this much attention. Did I mention that AmigaOS is still around? It's not free either. Someone out there is still willing to pay for an operating system most people have never heard of. AROS offers a way to use some AmigaOS programs without having to hand over money. Plus it's open source, which may leave you feeling more secure.

8. MenuetOS

Here's the thing about MenuetOS---it's small enough to fit on a single floppy disk. These were the flash drives of the 90s, and they only offered up to 1.44MB of storage. Considering many Linux distros have a hard time fitting on a 700MB CD, booting from a floppy is hard to fathom in this day and age.

MenuetOS is written entirely in 32/64-bit assembly language and is designed to run with very little overhead, even though it does support up to 32GB of RAM.

9. DexOS

Do all desktop operating systems feel a bit same-y? Here's a weird operating system that takes a different approach. Firing up DexOS will feel less like using the computer in keyboarding class and more like playing on a basic home game console.

Launching applications within DexOS feels vaguely like inserting a disc into an old Dreamcast. The experience feels seems more authentic if you're actually playing a game. And another cool thing? This free OS is also small enough to fit on a floppy. Try putting a version on a Raspberry Pi.

10. Visopsys

Like DexOS, Visopsys is the hobby project of a single developer. Check this out if you want another look at how much a single person can create.

The Visual Operating System (admittedly a name that could possibly apply to any OS with a desktop environment) has been in development since 1997. Impressively, it's not based on any pre-existing OS. That's not to say the project doesn't utilize pre-existing code. You will find common GNU tools here, and the icons may look familiar to KDE Plasma users.

Would You Use Any of These Free Operating Systems?

Most of them---no. Haiku developers don't run Haiku full-time. The Visopsys developer explicitly says the OS isn't as functional as Linux or, perhaps a more fair comparison, Syllable. DexOS is more an experiment than anything else.

That said, there are plenty of folks who prefer FreeBSD over Linux. illumos may not be a household name, even among FOSS lovers, but it has its uses. And did I mention using FreeDOS to play all those old DOS games?

But if you want to stick with a free operating system millions of people use everyday, there are many awesome Linux distributions to explore.