WEBVTT

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One of the coolest things I've discovered about circuits is

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circuitry can be an art form like if I have a creative idea, I can get that creative idea out using circuits.

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So if you have ideas, you can use technology to make those ideas come to life.

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Every input or output of a computer is effectively a type of information,

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which can be represented by on or off electrical signals

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or ones and zeros.

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In order to process the information that comes in as input, and to make the information that is output,

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a computer needs to modify and combine the input signals.

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To do this, a computer uses millions of teeny electronic components, which come together to form circuits.

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Let's take a closer look at how circuits can modify and process information that's represented in ones and zeros.

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This is an incredibly simple circuit.

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It takes an electrical signal, on or off, and it flips it.

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So if the signal you give it is a 1, the circuit gives you a 0,

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and if you give the circuit a 0, it gives you a 1.

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The signal that goes in is not the same as the signal that comes out, and so we call this circuit not.

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More complicated circuits can take multiple signals and combine them, and give you a different result.

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In this example, a circuit will take two electrical signals, now each one might be a 1 or a 0.

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If either of the signals coming in is a 0, then the result is also a 0.

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This circuit will only give you a 1,

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if the first signal and the second signal are both a 1, and so we call the circuit and.

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There are many small circuits like this that perform simple logical calculations.

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By connecting these circuits together, we can make more complex circuits that perform more complex calculations.

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For example, you can make a circuit that adds 2 bits together called an adder.

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This circuit takes in 2 individual bits, each one a 1 or a 0, and adds them together to calculate the sum.

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The sum can be 0 plus 0 equals 0,

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0 plus 1 equals 1, or 1 plus 1 equals 2.

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You need two wires coming out because it can take up to two binary digits to represent the sum.

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Once you have a single adder for adding two bits of information,

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you can put together multiples of these adder circuits side-by-side to add together much larger numbers.

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For example, here's how an 8-bit adder adds the numbers 25 and 50.

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Each number is represented using 8 bits, resulting in 16 different electrical signals that go into the circuit.

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The circuit for an 8-bit adder has lots of little adders inside of it, which together, calculate the sum.

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Different electrical circuits can perform other simple calculations like subtraction or multiplication.

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In fact, all the information processing your computer does is just lots and lots of small simple operations put together.

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Each individual operation done by a computer is so, so simple it could be done by a human,

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but these circuits inside computers are way way faster.

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Back in the day, these circuits were big and clunky,

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and an 8-bit adder could be as big as a fridge, and it would take minutes for them to perform a simple calculation.

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Today, computer circuits are microscopic in size, and way way faster.

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Why are smaller computers also faster?

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Well, because the smaller the circuit is, the less distance the electrical signal has to go.

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Electricity moves at just about the speed of light, which is why modern circuits can perform billions of calculations per second.

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So whether you're playing a game, recording a video, or exploring the cosmos,

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everything you could possibly do with technology requires lots of information to be processed extremely quickly.

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Underneath all this complexity is just lots of teeny little circuits that turn binary signals

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into websites, videos, music, and games.

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These circuits can even help us decode DNA to diagnose and cure disease.

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So what would you like to do with all these circuits?