The process of booting a Linux® system consists of a number of stages. But whether you’re booting a standard x86 desktop or a deeply embedded PowerPC® target, much of the flow is surprisingly similar. This article explores the Linux boot process from the initial bootstrap to the start of the first user-space application. Along the way, you’ll learn about various other boot-related topics such as the boot loaders, kernel decompression, the initial RAM disk, and other elements of Linux boot.
In the early days, bootstrapping a computer meant feeding a paper tape containing a boot program or manually loading a boot program using the front panel address/data/control switches. Today’s computers are equipped with facilities to simplify the boot process, but that doesn’t necessarily make it simple.

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