Build the kernel
Grasp the kernel basics
Just what is a kernel and why is it telling my computer what to do?
When you think of an operating system (OS) it ought to be an umbrella term for the ‘thing’ that’s responsible for everything your computer does after the BIOS/UEFI hands over control to the bootloader. For popular systems such as Windows and macOS it’s easy to lump everything together thusly. There’s no choice of desktops, no option to boot to a (real) command line and no real way to replace core applications (like
Explorer
and
Finder).
On Linux it’s clear that things are much more modular. The progression from UEFI to bootloader to kernel to login screen is much more demarkated. If you’re quick you can even identify the moment the kernel hands over to the initialisation system (for example,
systemd
or
runit).
Yet it turns out that every operating system has a kernel.