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When you connect devices together so

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that they can talk to each other,
you create what's called a network.

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One way to accomplish this is
with routers and switches.

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Routers are intermediary devices that
route data to its correct destination,

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meaning routers connect multiple
networks in order to move data around.

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Switches physically
connect local networks.

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And while switches have
a similar purpose to routers,

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switches are much less
intelligent than routers.

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Now let's learn about how switches
create a local network and

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routers connect those networks.

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A router is made to take
data packets destined for

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places outside the local network, and
move them from point A to point B.

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Just like clients and servers, routers
use protocols to talk to each other and

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figure out the more efficient
way to send each packet of data

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from one router to the next,
until the destination is reached.

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In order to work efficiently,
routing packets along the best path for

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their final destination,

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each router keeps information about other
routers in what's called a routing table.

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When a packet is received, a router
examines the packet and determines where

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it needs to go next, using
the information from the routing table.

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To do this, a routing table contains
at least three bits of information.

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The network ID,

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the cost, meaning how efficient the path
is that a packet is to be sent, and

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the next hop or gateway the packet will go
to on its way to its final destination.

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Another piece of hardware that bridges
the gap between computers is a switch.

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A switch is similar to a router
in that it also contributes

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to a network's efficiency.

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However, a switch manages
the flow of data across a network

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in a slightly different way, by physically
connecting devices together with cables.

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When a switch connects devices of
a school, computer lab or office together,

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it creates what's called
a local area network, or LAN.

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While you probably don't
have a switch at home,

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since there are few ports
built into your home router,

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you might be using one at school or
work, maybe even without knowing it.

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With switches creating networks and
routers connecting networks,

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we've created a wonderfully fast and
efficient process to move

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data around our community and world,
but that's not the end of the story.

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Stay tuned to learn about a few
more pieces of hardware and

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software that get the Internet all
the way to your laptop at your house.