Linux is a Unix like operating system, which will not mean anything to you if you only know Microsoft Windows. You will have more of a clue if you are familiar with macOS. When you enter the terminal app in macOS you are in a Unix like environment called Darwin, on which you can run the same software as you can run in Linux. I have been using Linux since its earliest days when you had to be a geek to put up with all the problems it through at you, but it was stable and virus-free. Nowadays malware affects all operating systems and Windows and macOS are generally more stable than Linux on a desktop or laptop computer. Linux was designed for the desktop, but succeeded as a server system and runs all of the fastest supercomputers on the planet and off-planet it runs the International Space Station and the Ingenuity Mars drone. The reason that I am writing a lot about Linux on a site about Repetitive Strain Injury relates to two Linux advantage from the 1990s that I have yet to mention: choice and gate-keeping. Linux encourages software developers to design everything except the kernel (the brain that communicates between the computer and its applications). Choice means that the operating system can be redesigned easily to help Repetitive Strain Injury sufferers. For example, you can easily set up keyboard shortcuts or menus to send the pointer to any point on the screen and so limit mouse pain. Gate-keeping means that you can safely download the applications that allow you to make these changes, because they are part of online repositories managed by the providers of your Linux operating system. There are similar applications for Windows or macOS, but they have to be downloaded from websites and that brings in the risk of accidentally downloading malware.
This page is designed to hold links to articles about Linux, which may make reference to RSI, but is primarily focused on general advice about the operating system and its applications.