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The internet

The internet is an ever-growing network of connected devices that spans the world.

These devices can share information with each other through cables that stretch between towns, cities, countries and continents.

The internet allows information to be sent from one part of the world to another part in less than one second.

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Internet hardware

So that we can view our favourite webpages, play games, watch videos and communicate on the internet, we need to have some internet hardware.

Look at the slideshow to find more about the role of each piece of internet hardware.

Image gallerySkip image gallerySlide 1 of 4, , Servers When you type in a URL or click on a hyperlink, a request is sent to a domain name system (DNS) server asking for the internet protocol (IP) address of the web service you are requesting. A DNS server stores the IP addresses of different web services.
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Sending data packets

When all of the data packets arrive at your computer, they may have actually come different ways.

Routers check to see which routes are the quickest before sending data.

This means that some of the data packets might travel different ways to get to your computer. This journey may involve travelling underground, through the oceans or in the air.

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How is the information reordered?

The data packets are all given a number before they are sent.

The computer uses these numbers to put the information back together in the right order.

Then, the web browser displays the webpage to you.

This process happens every time you request new information on the internet. What do you think takes longer?

  • The time it takes for the webpage to be sent
  • The time it takes to type in a webpage's URL

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Undelivered packets

If you go to a friend's house after school, your parent or guardian might ask your friend's parent or guardian to let them know that you've all got there safely.

Web servers do a similar thing with data packets.

Each data packet sends a message back to the web server to say it has arrived. If the web server does not get a message from a packet, it will resend that packet.

Both of these actions are part of the known as .

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Activities

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Computing - Dance Mat Typing. game

Build and test your computing skills with different levels of touch type challenges

Computing - Dance Mat Typing
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