Free software had become frustrated with the effects of the change in culture of the computer industry and its users. Software development for the GNU operating system began in January 1984, and the Free Software Foundation (FSF) was founded in October 1985. An article outlining the project and its goals was published in March 1985 titled the GNU Manifesto. The manifesto included significant explanation of the GNU philosophy, "Free Software Definition" and "copyleft" ideas. The Linux kernel, started by Linus Torvalds, was released as freely modifiable source code in 1991. The first licence was a proprietary software licence. However, with version 0.12
Tanenbaum–Torvalds debate titled "Can We Make Operating Systems Reliable and Secure?". While Tanenbaum himself has mentioned that he did not write the article to renew the debate on kernel design, the juxtaposition of the article and an archived copy of the 1992 debate on the technology site Slashdot caused the subject to be rekindled. Torvalds posted a rebuttal of Tanenbaum's arguments via an online discussion forum, and several technology news sites began reporting the issue. This prompted Jonathan Shapiro to respond that most of the field-proven reliable and secure computer systems use a more microkernel-like approach. Tanenbaum–Torvalds debate The Tanenbaum–Torvalds debate was