How do version numbers work in Linux distros?

[hop-frog]

SuSE: 7.0, 7.1, 7.2, 7.3, 8.0, 8.1, 8.2, 9.0, 9.1.
Mandrake: 7.0, 7.1, 7.1, 8.0, 8.1, 8.2, 9.0, 9.1, 10.0.
Slackware: 7.0, 7.1, 8.0, 8.1, 9.0, 9.1, 10.0.
What happend to all of the versions x.4, x.5, x.6, x.7, x.8, x.9? Is there an actual reason behind the version numbering or is it all marketing?

[Dark Ninja]

Originally posted by hop-frog
SuSE: 7.0, 7.1, 7.2, 7.3, 8.0, 8.1, 8.2, 9.0, 9.1.
Mandrake: 7.0, 7.1, 7.1, 8.0, 8.1, 8.2, 9.0, 9.1, 10.0.
Slackware: 7.0, 7.1, 8.0, 8.1, 9.0, 9.1, 10.0.
What happend to all of the versions x.4, x.5, x.6, x.7, x.8, x.9? Is there an actual reason behind the version numbering or is it all marketing?
Generally speaking, the second number is a minor version number -- only small changes or small packages updated. The first number changing means major things have changed. And, yes, there is an element of marketing to it. But, software versions can make a big jump like that. Not abnormal.

[squeegy]

I think I remember Slackware going from 4 to 7 for some reason or other.

[bwkaz]

It's kind of funny -- the actual Linux kernel gets enough changes made to it to warrant a new minor version number (as opposed to just a patchlevel) about once every couple of years. I don't know how long it's been since 1.X.X moved to 2.0.0...

But with distros, it can be about six months between one major version and the next... hmm...