Question

For example, netbeans has versions like 6.9.1; 7.0.0; 7.1.1 etc. Does the second number in the hierarchy mean improvement and the first is more about introducing new functionality, which makes it more likely to have bugs. So how do I interpret these version numbers, especially if I am willing to get the most stable version?

Answer 1

In the general case, version numbers have no fixed semantics. A common convention is to use a “major” version number to signify major changes, and “minor” version numbers to signify small changes, but this is not cast in stone. The recent release of Linux 3.0 is a good illustration — the major version number was incremented purely for PR value; the release was no more significant than earlier releases in the 2.xx series.

Some projects have a stable / unstable convention; odd-numbered minor version numbers are development versions, and the even-numbered minor versions are release versions. The Linux project uses this convention, as do Gnome and various other open source projects.

TeX has a playful version numbering convention of its own; it goes from 3.14, to 3.141, to 3.1415, to 3.14159 etc. (Hint: pi.)

See also http://en.wikipedia.org/wiki/Software_versioning