So, you know how some people have different names and like to be called by different names? Well, it's kind of like that with computer software.
There is a big group of people who made a type of computer software called "GNU", which is kind of like a fancy set of tools that help you use your computer. Another group of people made a type of computer software called "Linux", which is like the "brain" of your computer that tells it what to do.
But some people got upset because they thought that the name "Linux" didn't give enough credit to the "GNU" tools that were built into it. They wanted the software to be called "GNU/Linux" instead.
Other people disagreed, and thought that "Linux" was enough because it was the most important part of the software. They thought "GNU/Linux" sounded too long and complicated.
So, there's still a bit of a debate about what to call the software. Some people call it "Linux", some people call it "GNU/Linux", and other people just call it "Free and Open Source Software", which means that it is free for anyone to use and change.