Fundamentally, what is a PC architecture, what is the difference between x64, x86, ARM, whatever else etc. and why do they offer different benefits or drawbacks or performances
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ELI5 answer
They’re the basic instruction sets that the worker…the processor works off of. Some are reduced (RISC) and some are more complex (CISC) with mixes in between. (ELI5 explanation of RISC/CISC below)
These instructions make up the ‘core’ of what each program (make burger patty, fill drink) can utilize to accomplish tasks that combined together create a whole sequence (full meal to customer….or an application).
The software utilizes these basic instructions as part of the [ISA](https://en.wikipedia.org/wiki/Instruction_set_architecture) to know what it can do.
The fast food worker (CPU) utilizes the cheat sheet of the ISA which has broken down steps of what he can do with his arms, legs, eyes etc. To then execute the program (the customer order/application).
x86 and AMD x64 (x86-64) all stem from a common root and are considered CISCs. (complex)
ARM is a RISC. (reduced)
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Very high high level example
CISC will have an instruction called “Go to Bathroom” that does tons of things including going to bathroom, washing hands, doing your business etc.
RISC have basic instructions for moving your legs, arms, opening a door etc.
CISC instructions have a lot of overhead and sometimes do extra things that aren’t needed. When the program may only need to wash its hands, it may call the entire “Go to bathroom” and waste precious cycles doing bullshit.
RISC is much simpler and must have more expressive commands going to it and hence why its reduced. Its a reduced list of commands that can be utilized which makes it more efficent as it does less bullshit. But the size of the instruction sheet for ‘how’ to use the bathroom must now be larger
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