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The Internet is a network of
independent computers and

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other hardware devices connected together.

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You can think of this as a bunch of wires
that let computers around the world

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communicate with each other.

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Connected to these wires
are forests of other devices,

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which make the Internet work like servers,
routers, and switches.

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The primary network in core routers
around the world make up the backbone of

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the Internet, and support the exchange
of Internet traffic between countries,

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continents, and across oceans.

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Because of the diversity in hardware
used all over the Internet,

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everyone needs to work cooperatively.

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The developers behind the software
used on the Internet agreed to follow

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a set of rules called protocols,
when sending and receiving information.

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Let's look at what's involved when you go
to the homepage of your favorite website.

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For the purposes of this example,

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let's say your wirelessly connected
to the Internet at your house.

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After opening up a web browser and typing
in a URL, your browser uses a special

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protocol called HTTP or
Hyper Text Transfer Protocol.

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This is a set of rules for
asking for and getting webpages.

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But there's an even more basic set of
protocols under this, called TCP/IP.

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Which is short for Transmission Control
Protocol and Internet Protocol.

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These are the rules for sending and

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receiving any data whether it's email,
webpages or files on the Internet.

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Once you initial your request
TCP IP protocols take your request,

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webpages, videos, or emails and
break them into little packets of data and

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send them in the fastest way possible.

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From client to server and back again.

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The TCP IP protocols are a fundamental
part of the internet

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which we'll learn more about
later in another video.

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After you request a web page TCP IP
send your request wirelessly over

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radio waves either to a router or
directly to a wireless modem.

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If you have a router what
was a wireless request

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is now sent along an ethernet
chord to your modem.

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Your modem then sends the packets
along a coaxial cable or

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phone line to the outside of your house
where your internet service provider or

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ISP connects you to the Internet.

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The main network made of fiber
optic cables and computers.

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Once it reaches this point your request
is now sent from one server to another

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until it reaches the server that's
hosting the website you wanted.

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Then, the webpage you requested
is returned in just the same way.

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If this all happens correctly, the packets
of data arrive, are reassembled, and

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the web browser shows you
a perfect copy of the webpage.

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Usually this happens very quickly.

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Often in just a matter of seconds.

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So the internet has one job,
letting computers and

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other devices around the world
to talk to each other.

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But accomplishing that
job is no easy task.

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In the next few videos, let's look at each
aspect of the internet in more detail.