What Is Linux? A Plain-English Guide
Linux is the kernel behind a huge chunk of the internet, most supercomputers, Android, and millions of PCs — even if you never see its name.
Linux is the kernel that powers a huge chunk of the internet, most of the world's supercomputers, Android, and millions of personal computers — even though you'll rarely see it mentioned by name day to day.
The simple explanation
Just like Windows is Microsoft's complete operating system, "Linux" strictly speaking is just the kernel — the core piece that manages communication between the hardware and everything else. What people actually install on their computer (Ubuntu, Fedora, Mint) is that kernel combined with thousands of additional programs, packaged by different teams — hence the term "distribution."
Why do so many different versions exist?
Because it's open source (anyone can view and modify the code), different teams and communities have each built their own combination of kernel + software + philosophy, resulting in the hundreds of distributions that exist today.
Where does it show up without you noticing?
- Android: built on the Linux kernel.
- Most internet servers: a large share of the websites you visit run on Linux.
- Virtually every supercomputer in the world.
- Embedded devices: routers, smart TVs, and plenty of "smart" appliances.
Tip: never used Linux on a desktop but curious to try it? Our guide on trying it without installing anything is the safest starting point.
Frequently asked questions
Are Linux and Ubuntu the same thing?
Not exactly — Linux is the system's core kernel. Ubuntu is a 'distribution,' meaning that kernel combined with additional software and a specific setup, packaged by Canonical.
Does my Android phone really run on Linux?
Yes, Android is built on the Linux kernel, even though the day-to-day experience is very different from a traditional desktop Linux.
Is Linux free?
Yes, the vast majority of Linux distributions are completely free, with their source code publicly available to anyone.