Why Do Computers Use 1s and 0s? Binary and Transistors Explained.

It's a common theme throughout the modern world that everything in a computer's brain comes down to ones and zeros.

You've most likely heard that this code of ones and zeros is what's referred to as binary.

And while almost everybody knows that this is somehow related to what computers do, very few of us seem to understand what binary is or why computers use it.

If you want to know, then this video is for you, because it's actually a very simple concept.

And still quite fascinating, before we get to computers, let's talk about what binary itself is.

As it existed long before computers did, binary is nothing more than a system of counting.

To understand how it works, let's look at two other systems of counting, tally marks and the glorious base 10 positional that we all know and love today.

Tally marks are the simplest counting system imaginable, however many things you have, you put down that many marks, easy as pie, but not very efficient.

Meanwhile, base 10 positional, which is what we use today, uses a different symbol to represent different amounts of things.

With the numbers zero through nine, we can recognize that each symbol indicates a different amount of things.

If we need to represent something higher than nine, we add a digit to the left.

Roll its first digit back to zero and start over.

This system is very efficient compared to tally marks because each digit we add.

Exponentially increases the amount of things we can represent.

Because in this system we add a new digit every 10 things.

Each digit represents an increasing power of 10.

This is the number of ones we have, the number of tens, the number of hundreds, the number of thousands, and so on.

Now, this is probably something you already know.

But it's very important to keep it in mind when we talk about binary.

Now, binary works the exact same way as base 10 positional.

But instead of each digit going from zero to nine, it goes from zero to one.

Counting upwards in binary sounds like this: 0, 1, 10, 11, 100, 101, 110, 111, and 1000.

Because each digit of binary has only two values and not 10, each additional digit represents an increasing power of two, rather than an increasing power of 10.

So this is the number of ones we have, the number of twos, fours, eights, 16s, 32s, 64s, 128s, and so on.

Not nearly as efficient as base 10, but exponentially more efficient than tally marks.

Literally.

So now that we know how binary works, let's talk about computers.

Why did the first computer creators, as wise and intelligent as they are.

Waste their time with such an ineffective system of counting?

Well, it's because of a physical limitation on how computers work.

Everything a computer does comes down to what's known as micro transistors.

Simple, tiny, incy-bincy little switches that can either be on or off.

And can be flipped on or off with a very weak electrical charge.

The first goal was to get computers to count.

And to get them to count by using these switches, we could use the tally system.

Meaning the number of on switches equals the number of things we have.

Or we could use the much more efficient system of binary.

Where each switch represents a digit of binary.

Eight transistors using the tally system could represent a number as large as eight by turning all of them on.

With binary, we can represent a number as high as 255.

An on switch means a one.

And an off switch means a zero.

Now is a good time to mention that a single transistor.

Is what's known as a bit, which stands for binary digit.

A byte is eight of these bits in a row, which means any number between zero and 255.

So if binary is just a system of counting.

What do people mean when they explain how to spell things in binary?

Well, what they really mean is how to spell things with ASCII, the American Standard Code for Information Interchange.

Is a way to convert a computer's data, which can only be in numbers, and turn it into letters for humans to have an easier time to work with.

ASCII simply assigns a character to each value represented by a byte of binary.

Now, because a byte has eight digits of binary to work with, and eight digits of binary can represent up to 255 values.

ASCII had 255 letters and symbols to choose from.

More than enough for the entire alphabet.

Punctuation marks and other symbols.

For example, the corresponding ASCII number for an uppercase A is 65.

Now, 65 in base 10 is equal to 1,000,001 in binary.

So whenever you type in an uppercase A in a word program, a coding program, or a scripting program or whatever.

Somewhere there's a little tiny row of eight transistors arranged in the pattern of off, on, off, off, off, off, off, on.

Which represents 01000001 in binary.

Which is interpreted as 65 in base 10.

Which is converted by ASCII into an uppercase A.

You're likely starting to get a feel for the staggering amount of transistors required to write something as simple as a Facebook status.

Let alone all the different coding that your computer has to do to make the screen light up, play games, calculate massive values, and so on.

Well, long before we got to the point where your phone can play three-dimensional games.

It became clear that numbers as high as 255 just weren't going to cut it.

Regardless of how many bytes we had.

And it was a lot.

Even adding four fully active bytes together could only get a number as high as 1020.

To solve this problem, new computers were designed to recognize two bytes as one single number.

So now instead of referencing one line of eight transistors, computers could reference two lines.

Giving 16 digits worth of binary.

This was a huge help because it increased the amount of representable numbers exponentially from 255 up to 65,535.

When you hear people talking about the difference between 8-bit and 16-bit.

This is more or less it.

Now, that doesn't mean that a 16-bit system is exponentially that much more powerful.

Because your program isn't always going to be utilizing all of these numbers in each byte that it represents.

It just has the option to.

Which opens up lots of doors.

Well, this could go on for ages and ages, but I want to end this particular video right here.

So as not to be overwhelming.

In future videos, I will explain how computers use these numbers to decide which pixel is what color on your monitor.

What the different components of your computer are for.

And how hard drives store binary digits on a spinning disk rather than in transistors.

Thank you for watching.

And if you enjoyed this video, liking and subscribing is always a huge help.

Well, I've been enjoying making these instructional videos, I might move them to a different channel soon.

And continue doing comedic gaming related things on this channel.

So as not to confuse YouTube's search algorithm.

Which I think I am.