In this video, you will learn about CPU architecture fundamentals.
The first thing that we need to talk about is RISC versus CISC.
To perform instructions on a CPU, an instruction set is used.
And this instruction set is the basic way how a CPU is addressed.
The complex instruction set computer, or CISC, has fewer instructions per program, but the
each instruction can do a lot.
And CISC was introduced to make programming easier with fewer lines of code.
CISC is what you find on Intel CPUs.
There's a fundamentally different instruction set as well, which is known as the reduced
instruction set computer, or RISC, which has more instructions per program, but these instructions
are much simpler.
And RISC was introduced to make program execution faster, and to make it easier to optimize
hardware.
RISC is what you find on ARM, PowerPC, and other platforms.
And the most important thing that you need to know is that RISC-compiled programs don't
work on CISC and the other way around.
Now how does that relate to Linux?
Well, Linux can be used on different architectures.
And because of these fundamental differences between RISC and CISC, an application developed
for either platform cannot be executed on the other platform.
And as a result, you'll find Linux distributions for a specific platform, which can be Intel
or I86, and that doesn't work on ARM or AARC, and the other way around as well.
If you want to check the architecture that you are using, you can use the ARC command,
and that command will just print the architecture.
Let me show you.
So here I'm on my Ubuntu machine, and when I use ARC, there we can see AARC, and AARC
reveals that this is an ARM architecture.
Easy like that.
Do I also have an Intel?
So here I'm in a remote session to another computer, and this should be Intel-based,
and there we can see x86-64, which is 64-bits Intel.
And that's how you find out the architecture that you are currently using.