Why 0 and 1 ? Why not 0 , 1 and 2 ?

Question

Today, I saw the binary systems and I have a question about this subject. Why systems have 0 and 1? Why they not have 2 , 3 ? They can define 2 as +10V. And they can define 3 as +15V. Are there anybody who can tell me or can show resources why 0 and 1 ?

Answer 1

Yes you can definitely do that! In audio processing they commonly use signals with 5 different levels if I remember that correctly.
There have also been experiments with ternary (three-valued) computers (most famously Setun), but I think the idea of just having 0 and 1 is that it gives you a lot of leeway in your signal. Even if your hardware doesn't switch perfectly, it will usually be easy to distinguish. Of course now that everything is mass-produced there is no point in switching and no hope in getting more performance than binary computers.

Also, if you ramp up the voltage too high, your current might accidentally hop over to another wire (since modern transistors are just 14nm big)? I just made that up and I don't know much about electronics but that might be an issue too.

Answer 2

To make a long story short, it's 0 or 1 because it all relates back to switches. Originally, programmers had to set up these switches manually/physically, and computers were really huge then. It's how all of the logic works, and there is either flow(1) or not(0) through any of the given switches. Thankfully, with the invention of transistors, we were able to bring in the age of being able to program it so we didn't have to physically deal with the switches ourselves. This is also important to us, because all of this gave rise to these original programmers creating programming languages so that we can easily deal with the switches also.

There is so much more to that, but I'm not a history book, so better to go research it yourself. :D You may find interest in reading about quantum computing also.

*EDIT*

To give you an example, think about the stuff you're learning with programming. It seems complicated, but even something like:

IF these other things are switched on/off (true/false) THEN
take this path
ELSE
take another path

^As you can see, if you think about it, an IF/ELSE is nothing more than a switch (quite literally and physically). Switches controlling a bunch of other switches in order to create the flow that makes things happen.

Honestly, binary is pretty amazing considering what you can do with simply knowing the simple state of something else.

Answer 3

Likely because binary is just true or false in long chains.

Answer 4

Thank you. But what I am trying to say you is that why the computers made with 0 and 1 at the base. It can't be because of binary's mean.

Answer 5

Actually this is very simple

A micirocontroller consists of thousands tiny transistors. The state a transistor can take is either on, when it leaves electricity to pass, or its off. There is no other intermidiate condition. Even it is 0volts for logical 0and 230v for logical 1, thats it. It cant output something like100v.

And the big revolution of nanotechnology is exactly this. It can take an intermidiate state between 0 and 1.

See more on how a transistor works