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Welcome, in this video, I will introduce
you to the terms bit and byte.

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We will then identify some common
prefixes used for larger values and

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what they mean to you.

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You may have a mobile phone or a digital
camera that uses very small storage cards.

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This is called a microSD card, and
it's small enough to fit on your thumb.

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Ten years ago,
you can purchase one of these cards and

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you can take hundreds of high resolution
photographs before running out of space.

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Today, you can buy a thumb sized card and
take hundreds of thousands of photographs.

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How is this possible?

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To start, let's get a better
understanding of bits and bytes.

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A bit is the smallest unit of data or
information.

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It is short for binary digit,
which means it is either one or zero.

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You can think of this as a light
switch in the on or off position or

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the answer to a yes no question as true or
false.

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A byte commonly consists of 8 bits.

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Historically, it was used to store
a single character like the letter R or

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the number 7.

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We usually refer to a file
size in terms of bytes.

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For example,
this Python icon is 559 bytes.

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My resume stored as a word
processing file is 26,000 bytes.

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The movie Hidden Figures
stored on a Blu-ray disk is

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more than 39 billion bytes.

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There is a better way to refer to
these large numbers by using different

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prefixes before the word byte.

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For example, kilo means 1,000 or
1 followed by three 0s.

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You may have heard of kilo before.

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A kilogram means 1,000 grams.

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A kilometer or
kilometer means 1,000 meters.

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So instead of 26,000 bytes, I would
say that my resume is 26 kilobytes.

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Mega means 1 million or
1 followed by six 0s.

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My favorite song stored on a portable
music player is 4.7 megabytes.

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Giga means 1 billion, or
1 followed by nine 0s.

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A DVD of Hidden Figures
is 39.26 gigabytes.

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There are more prefixes for
even larger values.

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The largest widely
recognized prefix is yotta.

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A yottabyte is 1 septillion bytes,
or 1 followed by 24 0s.

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This is about 45 trillion
Blu-ray movie disks or

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1,000 years of worldwide Internet traffic.

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To house 1 yottabyte of data,

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you would need a data center roughly
the size of the state of Connecticut.

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Back to that microSD card for your phone.

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Today, you can buy a 256 gigabyte card for
the same price

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you would have paid for
a 256 megabyte card ten years ago.

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The difference is the card you buy today
stores 1,000 times the amount of data.

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In the next video, we will discuss the
different types of data you will use when

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writing computer programs.

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Stay tuned.