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In this video we are going to start
learning about basic computer network.

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We are going to start from the very basic,

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which is learning about what is computer
network and the function of computer network

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So what is computer network? In the simple term,

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computer network is used to help us
to share information between computer.

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For example, here I have a picture of computer
network. Here we can see that we have a laptop,

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computer, printer, playstation,
smartphone, and another computer

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And we can see that all of these devices is
connected to the router. Some devices connected

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to the router using cable, and some another
devices connected to the router using wifi.

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After all of these devices connected
to the router, now we have a computer

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network here. And all of these devices
now can share information each others.

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So this is a computer network, to help
us share information between computers.

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Now let’s talk more about how
computer network can help us

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In the past, before computer network exists,

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let’s say we have a room and in
this room we have six computer.

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For example all of this computer
want to print in the same time,

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before computer network exists,

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if we want to print, we need to have
a printer connected to our computer.

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So if we have six computers like this, we will
need six printers that connected to each computer.

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We need a printer in computer 1, computer 2,

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computer 3, computer 4, computer 5, and also
we need a printer in computer 6 like this.

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Now let’s imagine, we just have six computers
right now, and we need six printers that

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connected to each computers. How if we have
100 computers, so we will need 100 printers right?

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This is absolutely not cost effective.

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But now, with computer network, we don’t
need to buy a printer for each computer.

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We just need to have 1 printer that connected to
computer network, and then all of computers can

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print with this printer using computer network.
Doesn’t matter if we have 10 computers,

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50 computers, or even 100 computers,
we just need to have 1 printer

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that connected to the computer network, and all
of that computers, can print using this 1 printer.

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So this is one of the function of computer
network. Absolutely, this is help us much right?

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Another example of the function of computer
network is to share data between computers.

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In the past, or actually now we still use this
method. You know about flashdisk right? We can

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use flashdisk to share data from
one computer to another computer.

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For example we want to share data
from the computer to the laptop.

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Before computer network exists, we need
to connecting a flashdisk to the computer,

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then copy the data from the computer
to the flashdisk. When this is done,

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we need to bring the flashdisk to the laptop.
And then now we can copy the data from the

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flashdisk to the laptop. Now we have successfully
share the data from the computer to the laptop.

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But we have a problem here. Which is we need
to bring the flashdisk from the computer to the laptop.

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Let’s imagine that the computer
is in the 1st floor in the building,

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and the laptop is in the 10th floor.  So
we need to walk to bring this flashdisk

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from the computer to the laptop.
This is absolutely not efficient!

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But now, if we use computer network, we don’t need
to do that. We can share data between computer

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and laptop using computer network, as long as
computer and laptop is connected to the same

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computer network. In this example, computer
and laptop is connected to the same router,

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so absolutely, we can share data
between this computer and laptop.

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So this is some of example how computer network
can help us. First we can use computer network

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for sharing a printer, and also we can
use computer network to sharing data.

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Besides these two example, we usually use
computer network to access the internet.

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For example, we can access facebook.com from
the smartphone here. When we access facebook.com

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from the smartphone like this, we already use a
computer network. Why? Because our smartphone is

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connected to the router using wifi, and the router
is connected to ISP or

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Internet Service Provider, and then
the ISP is connected to the internet.

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And absolutely, we have a facebook.com
that also connected to the internet.

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When we access facebook.com from the smartphone,
the packet will be forwarded to the router,

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from the router will be forwarded to the ISP,
from the ISP will be forwarded to the internet,

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and somehow the packet will be
forwarded to the facebook.com.

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So this is how we use computer network to
access facebook.com from our smartphone.

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Not only facebook.com, when we
access internet like youtube,

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twitter, or when you watch this
video, you are using computer network!

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Okay I hope you now understand what is computer
network and how computer network can help us.

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In the next video, we are going to
learn about the most simple computer network.

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Thankyou for watching
and see you on the next video!