How do computers know what to do with binary 1’s and 0’s?

Question

I’m very interested in learning how computers work, but can’t seem to find the exact information I’m looking for. My understanding is, and **please** correct me if I’m wrong, is that if you press the letter “A” on a keyboard, a circuit underneath will close which sends electricity to wires, and based on the combination of voltages on the wires, the computer outputs an “A”. But how does the computer know what do to with voltages? What do the voltages represent? At what point does any of this information get converted into binary, and once it does, what happens?

I don’t expect someone to be able to explain this like I’m five. For me, it’s a difficult, but really interesting subject. Any clarification and dumbing down is appreciated! I’m really hoping to get a better grasp on my understanding of all this.

Edit: I should’ve made the title “How do computers work?” Still wondering how computers know what to do with 1’s and 0’s, though.

In: 0

Answer 1

They don’t really work with single 1’s and 0’s. You could build a computer that does but generally they’ll use several in a row. You have several metal tracks carrying (or not carrying) current. On is 1. Off is 0.

If you have 8 tracks, there are 256 combinations of off and on each representing a different number. A lot of old computers worked this way. This is what “8-but” means when referring to a processor. 16 bit processors can deal with 65535 different combinations, 32 bit with 4 million or so but the principle is the same.

So, what do we do with these numbers? Well, we can access memory. Memory chips have a bunch of “address” pins, and a bunch of “data” pins. Send a number to the address pins and the memory chip sends a number at that location from the address pins to the processor.

The processor sends a request for data at address 00000000, and looks at these in increasing order. It receives, for example, 00101100. This means look at the next 2 memory locations, and add them. Then it might receive 01011111 which means “store this number at memory location given by the next memory location”. The numbers here are just made up and chosen arbitrarily by me but real processors have numbers assigned arbitrarily my a designer. There’s no particular reason to choose any number.