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In this video we'll talk about hardware essentials.

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So you need to have a little bit of understanding of computer hardware in order to address it

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the right way from the Linux operating system.

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Computer hardware ensures that you can use computers for useful purposes.

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And in the computer hardware there is the Central Processing Unit, or CPU, which receives

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and executes instructions that are issued by computer programs.

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It's a core component of your computer.

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And it works with Random Access Memory, or RAM, which holds data that currently running

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computer programs are using.

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RAM is important, and in many cases you'll never have enough of it.

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The hard disks are the components that are used to permanently store data.

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Most computers have at least one, and many computers have more hard disks.

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And peripherals are typically included to perform other operations as well.

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And the type of peripherals really depend on the functionality that you are using your

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computer for.

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To work with the hardware we have the operating system.

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The operating system is defined as the main program that makes your computer work.

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Linux is an operating system, Windows is an operating system, and there are other operating

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systems.

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And the operating system as such performs different functions.

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It controls the hardware, it manages files, it runs programs, and it provides a user interface.

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These are the core functions of the operating system.

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Now the operating system needs to communicate with the hardware, and in order to do so it

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uses drivers.

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Without a proper driver, which we call kernel modules in Linux land, the computer cannot

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do anything with the hardware.

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The Linux drivers can be provided by the open source community or by the hardware vendor.

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We call those proprietary drivers.

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Now sometimes you may find yourself in a situation where your computer works with custom hardware.

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That means hardware that is not based on a PC-like architecture.

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Your laptop, your server, and everything else is based on PC-like architecture, but on Linux

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embedded systems are commonly used as well.

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Embedded hardware systems have all the hardware on one single board, and they need to be programmed

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in a different way.

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You can think of appliances like airplane video systems or microwave ovens, and there

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are many more.

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Working with embedded systems is significantly different.

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An operating system is created, and it's flashed to a CMOS chip instead of installed on the

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hard drive of the computer.

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And on embedded Linux, specific architectures are often used.

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To build an image for specific architectures, you need to go through a process that is known

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as cross-compilation.

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That means that you prepare the image on one platform, typically that would be your laptop,

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and you flash it to another platform, and that would be the embedded device.

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A commonly used Linux-based platform to do so is Yocto.

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And Raspberry Pi is a common embedded hardware system.

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These are available for not too much money.

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It's nice to play if you want to work with embedded hardware.