Imagine an operating system (OS) that runs like a train, hardly ever crashes and costs nothing to install. Come the day, you may say. But such an OS is already with us - Linux OS - which has grabbed headlines for the past year.
Linux will run on almost any PC and most Macs. Like Windows and any other kind of OS, it acts as a computer's internal logic, controlling the interpretation of orders made by whoever moves the mouse and taps the keys.
Linux has at least 10 million users. That's not many compared with Windows users, but Microsoft feels beleaguered because Linux's user base is expanding fast and the OS already dominates the Internet service provider arena.
You might assume Linux was created by a huge company with scores of programmers working on it. In fact, it emerged under strangely low-key circumstances, mostly through the effort of Linus Torvalds, who developed it when still a student at the University of Helsinki in 1991.
The boy wonder developed Linux from Unix, a command-based OS long a fixture in academic computing departments and big corporations, and the lingua franca of the Internet, despite every attempt by Microsoft to budge it.
Rather than patenting the system for his own gain, Mr Torvalds, in saint-like fashion, publicised the source code, the usually secret 'recipe' that determines how the software works, so that other programmers could copy, refine and develop it.