The same happens with Linux, code for which was released in 1991. People used to call Linux a synonym for GNU, much like Windows became a synonym for the PC operating system. But they are not the same thing, are they?

Stallman: I'm not sure what you mean by "the same." Windows is the official name (not just a synonym) for a user-subjugating, proprietary operating system developed by Microsoft. Linux, however, is not an operating system, just a piece of one. Linux is a kernel: the component of an operating system that allocates the machine's resources to the other programs that you run. It was first released in 1991 as non-free software: its license did not allow commercial distribution.

In 1984, I launched the development of the GNU operating system, whose goal was to be free software and thus permit users to run computers and have freedom. The GNU Project undertook a job so big that even most of my friends said it was impossible. In 1992, the GNU system was complete except for the kernel. (Our own kernel project, started in 1990, was going slowly.) In February 1992, Linus Torvalds changed the license of Linux, making it free software.

The kernel Linux filled the last major gap in GNU; the combination, GNU/Linux, was the first free operating system that could run on a PC. The system started out as GNU with Linux added. Please don't call it "Linux;" if you do that, you give the principal developer none of the credit. Please call it "GNU/Linux" and give us equal mention.

The Free Software Foundation has recently issued the second draft of the GNU general public license version 3 (GPLv3). What are its enhancements and what users could expect from adopting it?

Stallman: We published the official, final text of GPL version 3 in June, and many programs have since been released under it. The basic goal of the GNU General Public License is the same in version 3 as it always was: defend the freedom of all the users. The changes are in the details.

Linus Torvalds told he thinks "the GPLv2 is a superior license," but there's "something like 50 different open-source licenses, and in the end, the GPLv3 is just another one." Does Linus collaborate with you or GNU on free software development?

Stallman: The fact that Torvalds says "open source" instead of "free software" shows where he is coming from. I wrote the GNU GPL to defend freedom for all users of all versions of a program. I developed version 3 to do that job better and protect against new threats.

Torvalds says he rejects this goal; that's probably why he doesn't appreciate GPL version 3. I respect his right to express his views, even though I think they are foolish. However, if you don't want to lose your freedom, you had better not follow him.

Microsoft has recently claimed that free software like Linux, OpenOffice and some e-mail programs violate 235 of its patents. But Microsoft also said it won't sue for now. Is this the start of a new legal nightmare?

Stallman: Software patents - in those countries foolish enough to authorize them - are a legal nightmare for all software developers. About half of all patents in any field belong to mega-corporations, which gives them a chokehold on the technology. In countries that allow software patents, that happens in software too.