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In this video, you will learn about CPU architecture fundamentals.

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The first thing that we need to talk about is RISC versus CISC.

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To perform instructions on a CPU, an instruction set is used.

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And this instruction set is the basic way how a CPU is addressed.

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The complex instruction set computer, or CISC, has fewer instructions per program, but the

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each instruction can do a lot.

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And CISC was introduced to make programming easier with fewer lines of code.

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CISC is what you find on Intel CPUs.

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There's a fundamentally different instruction set as well, which is known as the reduced

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instruction set computer, or RISC, which has more instructions per program, but these instructions

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are much simpler.

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And RISC was introduced to make program execution faster, and to make it easier to optimize

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hardware.

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RISC is what you find on ARM, PowerPC, and other platforms.

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And the most important thing that you need to know is that RISC-compiled programs don't

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work on CISC and the other way around.

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Now how does that relate to Linux?

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Well, Linux can be used on different architectures.

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And because of these fundamental differences between RISC and CISC, an application developed

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for either platform cannot be executed on the other platform.

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And as a result, you'll find Linux distributions for a specific platform, which can be Intel

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or I86, and that doesn't work on ARM or AARC, and the other way around as well.

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If you want to check the architecture that you are using, you can use the ARC command,

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and that command will just print the architecture.

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Let me show you.

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So here I'm on my Ubuntu machine, and when I use ARC, there we can see AARC, and AARC

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reveals that this is an ARM architecture.

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Easy like that.

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Do I also have an Intel?

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So here I'm in a remote session to another computer, and this should be Intel-based,

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and there we can see x86-64, which is 64-bits Intel.

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And that's how you find out the architecture that you are currently using.