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- [Instructor] Yay for Grub,

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the Grand Unified

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Linux bootloader.

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Now when you power on your system,

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there's probably some sort of power on self test

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in the BIOS and things like that,

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but the system will start up the bootloader.

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GRUB will be in a special place in the disc

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for the system to be able to find it.

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That gets started and it's GRUB's job

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to load the kernel into RAM

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and also commonly with Linux,

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there's going to be a fairly small,

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little file system called the initial root file system,

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sometimes called the Knit rd.

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It used to be a RAM disc.

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So GRUB loads those two files in memory

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and then starts up the kernel,

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passing to it the kernel command line

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that's set in GRUB's config file

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and GRUB has some nice features,

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including being able to be interrupted

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before it starts to kernel.

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GRUB is quite powerful.

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GRUB is built with support for some file systems

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so that it can read your disc

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and look for files by name.

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Some bootloaders can't do that.

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That means, for example,

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with the interactive nature of GRUB,

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you can get it to find the name of a kernel

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for you if you had a typo.

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There's quite a lot involved with GRUB.

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If you do a man minus K grub, the K means keyword.

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You can see things related to GRUB.

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There's a lot going on.