Kernel Numbering

Each new linux kernel is numbered using three numbers in an x.x.x format. The first number represents the version of the kernel, the second number corresponds to the major changes in that specific release, and the third number corresponds to the minor changes. The version number rarely changes, as there have only been 3 versions of the kernel since 1991 (and version 3.0 was only released to celebrate the kernel's 20th anniversary). Minor changes and release candidates for the kernel occur often, with the major changes not occurring as frequently. The development and numbering of the kernel has slowed down significantly in the recent years.