If there are no different versions of Linux then what is the meaning of 'Linux 4' and 'Linux 9'?

Answer:
There is no "Linux 4" or "Linux 9." I'm not sure where people get these numbers from. They could be reading the version numbers of a particular distro (such as Red Hat Enterprise Linux 4 or SUSE Linux Enterprise Server 9). However, the Linux kernel is developed centrally and then subsequently used by all of the distribution vendors. The current stable version of the Linux kernel is 2.6.30; the 2.6 kernel line is expected to continue indefinitely.
First answer by Idisjunction. Last edit by Idisjunction. Contributor trust: 805 [recommend contributor recommended]. Question popularity: 1 [recommend question].