What is the Linux Kernel

The kernel is the most important feature of what we commonly refer to as the 'Linux technological marvel'.

In IT terms, the kernel is both the heart and brain of an operating system, as it controls the fundamental hardware. The kernel is the core of the operating system, possessing many essential functions such as virtual memory, multitasking, shared libraries, demand loading, shared copy-on-write executables, and TCP/IP networking capabilities.

The origin of the Linux kernel can be traced back to 1991, when Finnish university student Linus Torvalds wrote and first released Linux. Although the Linux ecosystem has since grown far beyond Torvalds himself, he still maintains control over the Linux kernel and is the sole copyright holder of the Linux name. Since the release of Linux version 0.12, Linux has been licensed under the GPL (General Public License) free software license.

The Linux kernel itself is not an operating system; it is a component of a complete operating system. Linux distributors such as Red Hat, Novell, Debian, and Gentoo all adopt the Linux kernel and then add more tools, libraries, and applications to build a complete operating system.

Linux distributors typically customize the base kernel according to their needs. In some cases, different Linux versions incorporate features and support into their kernels that are not present in the mainline kernel. For example, Red Hat backported some features of the 2.6 kernel to its own 2.4.x kernel. Another example is the Ubuntu Linux version, which recently added support for Sun T1 processors to Ubuntu's 2.6.15 Linux kernel, a feature not yet present in the mainline kernel.