Linus Torvalds on Linux

“We could adopt the even/odd numbering scheme that we used to do on a minor number basis, and instead of dropping it entirely like we did, we could have just moved it to the release number, as an indication of what was the intent of the release. … We'd have an increasing level of instability with an odd release number, depending on how long-term the instability is. … With the odd numbers going like: 2.6.: still a stable kernel, but accept bigger changes leading up to it (timeframe: a month or two). 2..x: aim for big changes that may destabilize the kernel for several releases (timeframe: a year or two) .x.x: Linus went crazy, broke absolutely everything, and rewrote the kernel to be a microkernel using a special message-passing version of Visual Basic. (timeframe: "we expect that he will be released from the mental institution in a decade or two").”