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At it's core how does a computer actually work?

This is something that's really confused me, I know a lot about computer science but one thing I can't figure out is that how does a computer actually work:
- How does a CPU actually process instructions; like how does it turn data into something else, physically how because it isn't magic.
- How does data get from RAM into the CPU, because I know an instruction can be sent from the CPU to fetch it into it, but how does new data coming into RAM cause something else to move; physically how do the electrons move because of the instruction sent, how does the instruction physically cause the electrons to move.
- Tying into number 2 how can an input device send commands such as characters and spaces to the CPU, for example how does a keyboard send the binary data from a character set to the CPU and how does a CPU recognize this binary is a character?
Boolean algebra expressed physically via silicon logic gates.
Reply 2
Original post by beefybarry
This is something that's really confused me, I know a lot about computer science but one thing I can't figure out is that how does a computer actually work:
- How does a CPU actually process instructions; like how does it turn data into something else, physically how because it isn't magic.
- How does data get from RAM into the CPU, because I know an instruction can be sent from the CPU to fetch it into it, but how does new data coming into RAM cause something else to move; physically how do the electrons move because of the instruction sent, how does the instruction physically cause the electrons to move.
- Tying into number 2 how can an input device send commands such as characters and spaces to the CPU, for example how does a keyboard send the binary data from a character set to the CPU and how does a CPU recognize this binary is a character?
You clearly don't.
Original post by Tootles
You clearly don't.


It is possible to know a lot of computer science without understanding how a computer works on the lowest of levels. Loads of computer science does not even go into the physics of how computation works.
Reply 4
Original post by ChaoticButterfly
It is possible to know a lot of computer science without understanding how a computer works on the lowest of levels. Loads of computer science does not even go into the physics of how computation works.
There's a difference between boolean algebra and physics of computation, though.
Original post by Tootles
There's a difference between boolean algebra and physics of computation, though.


Boolean algebra is the maths of how a CPU works. The transistors form the logic gates and the logic gates work acording to boolean algebra. So if you want to understand how a modern day digital computer works you are going to have to get to grips with the maths that describes it.

There is also a lot of computer science that goes nowhere near any of this. It's pretty much irrelevent to most programmers. Even Lower level languages such as C++ are so far removed from this that you don;t even need to think about it.
(edited 5 years ago)
Reply 6
Original post by ChaoticButterfly
Boolean algebra is the maths of how a CPU works. The transistors form the logic gates and the logic gates work acording to boolean algebra. So if you want to understand how a modern day digital computer works you are going to have to get to grips with the maths that describes it.
Thanks, I knew that. I'm pretty good at boolean algebra, myself, and have played with digital electronics some. I was pointing out that "physics" isn't usually used as shorthand for "physical implementations".
Reply 7
Original post by beefybarry
This is something that's really confused me, I know a lot about computer science but one thing I can't figure out is that how does a computer actually work:
- How does a CPU actually process instructions; like how does it turn data into something else, physically how because it isn't magic.
- How does data get from RAM into the CPU, because I know an instruction can be sent from the CPU to fetch it into it, but how does new data coming into RAM cause something else to move; physically how do the electrons move because of the instruction sent, how does the instruction physically cause the electrons to move.
- Tying into number 2 how can an input device send commands such as characters and spaces to the CPU, for example how does a keyboard send the binary data from a character set to the CPU and how does a CPU recognize this binary is a character?

0 or 1
Original post by Tootles
Thanks, I knew that. I'm pretty good at boolean algebra, myself, and have played with digital electronics some. I was pointing out that "physics" isn't usually used as shorthand for "physical implementations".


Well physics and engineering overlap. The devlopemnt of computers is very much applied physics. As with most stuff you just have to work out which is the most useful approach for the problem presented. In this case someone was asking how a computer worked on the lowest of levels.

I chose to go to the level of the physical logic gates where you can imagine lots of tiny logic gates all clicking away according to the rules of Boolean Algebra. Maybe OP wants the quantum mechanics behind the transistors, but I doubt it. That wouldn't really help much imo.

You on the other hand just decided to call the OP an idoit even though a lot of computer science goes nowhere near any of this. It's pretty much irrelevent to most programmers. Even Lower level languages such as C++ are so far removed from this that you don;t even need to think about it.
(edited 5 years ago)
At the most fundamental level, imagine asking questions that that can only be answered yes or no, but billions and billion of time per second.
Reminding me of my first year digital electronics module of which my main reaction was "I didn't sign up for this". Came in useful later in life though when I did a machine learning module in another degree.
(edited 5 years ago)
AUB and !A
Reply 12
Magic.
If you care enough to read a book on it, I would heavily recommend: "CODE: The hidden language of computer hardware and software", it teaches you all these basics of how a computer works at a very basic level.

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