The Linux 3.x kernel family is no more. Long Live Linux 4!
The Linux 3.x kernel family first officially debuted on July 22, 2011. Linux 3.0 was the first major version change for Linux since the 2.6 kernel debuted in December of 2003. While Linux 2.6 was a major milestone that signified a break with the past, Linux 3.0 really was just the renumbered Linux 2.6.40 kernel. In the same manner the Linux 4.0 kernel is the continuation of Linux 3.x and is the renamed Linux 3.20.