Torvalds' Linux kernel is combined with the GNU system, creating a fully functional, free operating system. This combination, which Stallman insists be called GNU/Linux, becomes immensely popular.

While both advocate for free software, Torvalds often takes a more pragmatic approach, focusing on technical functionality and user convenience, while Stallman emphasizes the ethical imperative of software freedom.

Stallman insists on the term 'GNU/Linux' to acknowledge the GNU project's significant contribution to the operating system. Torvalds and many others prefer simply 'Linux', leading to ongoing debate.

Both Torvalds and Stallman occasionally comment on each other's work and views, sometimes publicly, reflecting their different perspectives on software development and freedom.

Despite their philosophical differences, the collaboration between GNU and Linux has been incredibly successful, creating a powerful and widely used operating system that embodies many of the principles of free software.