"In computing, a kernel is the low-level software that handles communication with hardware and general system coordination. Aside from some initial firmware built into your computer's motherboard, when you start your computer, the kernel is what provides awareness that it has a hard drive and a screen and a keyboard and a network card. It's also the kernel's job to ensure equal time (more or less) is given to each component so that your graphics and audio and filesystem and network all run smoothly, even though they're running concurrently." (See How to compile a Linux kernel in the 21st century )