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In order to talk to machines, you have to
speak in their language.

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Early on, we figured out ways to extract
code from machine languages.

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But, in order to step forward,

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we must step down to some lower level
machine code.

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The binary numbering system is similar to
the decimal numbering system you're

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already use to in many ways.

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The principles behind the systems are
similar, but

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obviously there's some differences as
well.

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Let's start with some names you may
already be familiar with.

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A bit is the smallest unit in binary, and
it can either be a zero or a one.

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If you put eight bits together it's a
byte.

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Both the decimal and binary numbering
system, are positional numbering systems

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meaning, the position of the numbers
indicate the relative value.

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Let's look at an example.

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In the number 1,234, the 1 is worth 1000,

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the 2 is worth 200, the 3 is worth 30 and
the 4 is worth 4.

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If you switch these numbers around, their
relative values will also switch around.

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The decimal system accomplishes this place
value by using 10 as the base, and

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increasing the power each time you step to
the left, or 10 the 0, 10 to the 1,

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10 to the 2, are the ones, tens, and
hundreds place.

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This same process happens in binary.

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Only it uses two as the base instead of
ten so the first position is two to zero

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the second position is two the first, the
third position is two to the second and

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the fourth position is two to the third,
representing the ones,

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twos, fours and eights place.

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Now, let's use our knowledge of place
value to find out

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what this bite represents.

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Don't be shy, take a guess.

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[SOUND] That's right, it's 1.

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Here we've turned on the first bit which
represents a 1 or

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a 0 meaning this equals 1.

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Let's try another, what about this bite?

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Here we've turned on the second bit which
represents two, so this bit equals two.

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And, what about this one?

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Here we've turned on the first two bits,
the two and

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the one, because two and one equals three.

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This represents three.

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[BLANK_AUDIO]

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Let's skip ahead a little bit.

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What do you think this byte will
represent?

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Here we have the 8 and

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the 2 bits turned on, so this represent
10, because 8 plus 2 is 10.

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Now, let me assure you none of the
languages we teach here at

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Treehouse use the binary numbering system.

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But, it's important to know where your
data is going, and

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what it looks like to a computer.

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In the next video,

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we'll look at a laptop tear down to see
what data storage hardware looks like.