The Internet – How It Works

The Internet – How it Works.SE’s Internet guide, nr 32Version 1.0 2014Hasse NilssonThe text is protected under copyright law and is provided with the license Creative Commons Attribution 2.5 Sweden. License can be foundat creativecommons.org, currently on page: lcode.The illustrations are protected by copyright law and provided with thelicense Creative Commons Attribution-Share Alike 2.5 Sweden. Licenseterms can be found at creativecommons.org, currently on page: hen revising the work, .SE logos and .SE graphic elements shall beremoved from the processed version. They are protected by law andare not covered by the Creative Commons license as above. .SE carbonoffsets for their carbon footprint and supports the climate initiativeZero Mission. See www.zeromission.se for more information on ZeroMission.Author: Hasse NilssonEditor: Hasse NilssonProject leader: Jessica BäckIllustrator: Petra SegerbergFirst edition, first printing.Print: Danagårds LiTHO, Ödeshög, 2014-05-15Special thanks to: Tomas Ribba and all others who contributed.ISBN: 978-91-87437-10-6Organisation number: 802405-0190Visiting address: Ringvägen 100 A, 9 tr, StockholmMailing address: .SE Box 7399, 103 91 StockholmTelephone: 46 8 452 35 00, Fax: 46 8 452 35 02E-mail: info@iis.se www.iis.se.SE (The Internet Infrastructure Foundation) is responsible for theinternet’s Swedish top level domain. .SE is a charitable organizationthat works for a positive development of the internet in Sweden.All of .SE’s internet guidesYou can find all of .SE’s internet guides on www.iis.se/guider. You can ordera subscription of newly produced guides by sending your name and addressto publikationer@iis.se.

How do you use the internet?

Where is the internet?You have the internet, forexample, in your computer,mobile and your tabletof course.

But really, the internet is theworld’s largest network ofcomputers and exists all overthe planet.

Except in some remote places.

Okay, but how does it allfit together?

At home you might have asmall network without wiresbut it is still connected to theinternet by a cable.

Usually your home isconnected to the internet bya wire that is buried in theground to a cabinet wheremany wires are connected toa large internet cable.

You can also connect with amobile, without wires, and thensignals are sent to and fromyour mobile through a mobilemast which is then connectedto an internet cable.When you use the internet,your device is part of theinternet network.

The internet cables in theground form a network.These small networks areinterconnected with largernetworks and then further allover the world with the helpof wires that send informationsuper fast.

Are you wondering how fast?Nearly five times around theEarth per second!Because it’s light in theselarge internet cables thatsend the information, whichwe usually call internettraffic.

Can I send a cheese sandwichover the internet?

No, because the things thatare sent on the internet arecalled digital information andare made up of ones and zeros.Computers and computerprograms translate the onesand zeros so that you can see,hear and use the information.

If you want to: check out web pages, send and receive messages, create a site and write a blog, upload pictures, play games, watch movies, listen to music, and many other things

On the internet, there aremillions of computers calledservers. Contained in theservers are things like websitesor huge game worlds.It is common to have manyservers connected in largedata centers. But it’s alsopossible to have a server athome or at work.

The large computers andservers can talk with eachother, but they do not speak ina normal language, like English.Instead, they send numbers andcodes to each other.The good thing about this isthat a computer in Swedencan understand a computer inJapan even though the peoplespeak different languages.

If you want to check out awebsite, a kind of questionis sent from your computerto a server on the internetthat answers. The serverthat answers can be locatedanywhere in the world.Then the website is sent toyour computer and you cansee it and click on it.

How can a website find theright place on the internetand arrive on my computer?That is because all appliancesthat are connected to theinternet, like computers,mobiles and servers, havetheir own address.

It’s like the house you live in.It also has its own address sothat you can receive mail andpeople can visit you.

You can also say that internetaddresses are like telephonenumbers. The right numbersin the right order make thecomputers and mobiles able tofind each other on the internet.It’s like calling a telephonenumber and having someoneanswer.

Do you remember thatcomputers on the internet talkwith numbers and codes?Good! An address to acomputer that is connected tothe internet can look like this.The number addresses on theinternet are called IP addresses.

Complicated, right?You can’t read and rememberso many numbers and points!

This is why computerstranslate number addressesto letters. As people, weread and talk with words andletters, not with numbers.

If you write or click on alink to a web address, yourcomputer then contacts theright server with help of theinternet’s address registry.But actually, the addressis translated to a set ofnumbers and points.

Addresses on the internetcan be short like iis.se or longlike www.tekniskamuseet.seAn address with lettersinstead of numbers is calleda domain name.It is the servers that havedomain names, not thecomputer, mobile or tablet.

There are around 250 milliondomain names in the world.In other words, there isunbelievably much todiscover on the internet.

Addresses that end in .se havea connection to Sweden. Andthere are around 1.3 million .seaddresses.There are also other addressesthat end with two letters thatshow which country a site hasas its home.

To take some examples, Danishwebsites often have .dk atthe end, while many sites inFinland end with .fi and inNorway they use .no.All the countries in the worldhave a similar letter code.

The abbreviation at theend of an internet address,like .se, is called a top-leveldomain and there are over300 different top-leveldomains in the world.

But there are more types ofaddresses on the net! Have youseen addresses that end in .com,.net or .org? These are addressesthat do not indicate where in theworld the server is located butwhich can be found anywhere.The island of Niue has the countrytop-level domain .nu, which is usedin the same way since the word“nu” means “now” in both Swedishand Dutch.

Now to summarize a bit:The net is easy to use becausethere is a system with addressesso that you can always find theright way on the internet.

There you go! Now youknow a little more about theglobal computer networkcalled the internet, which isused by 2.7 billion people.

Every new .se address contributes to the development of the internet.SE (The Internet Infrastructure Foundation) is responsible for the internet’s Swedish top-level domain and administersthe registration of domain names under .se. The surplus from the registration fees for domain names are invested in internetdevelopment that benefits all internet users, through things like this internet guide!

.SE (The Internet Infrastructure Foundation) wants to promote a positivedevelopment of the internet in Sweden in different ways. One of our mostimportant objectives is that everyone should be able to participate in thepossibilities of the net. For this reason, we publish educational internetguides in various exciting topics. There are practical guides for those whowant to start blogging, technical guides for those who wonder how thee-mail one sends reaches the right recipient, and guides that explain whoactually decides on the net.SE Internet guides are free. Order or read them online: www.iis.se/guider.SE (The Internet Infrastructure Foundation)Box 7399, SE-103 91 Stockholm, SwedenTel: 46 8-452 35 00, Fax: 46 8-452 35 02Corporate Registration Number 802405-0190, www.iis.se

The Internet – How it Works.SE’s Internet guide, nr 32 Version 1.0 2014 . But really, the internet is the world’s largest network of computers and exists all over the planet. . listen to music, On the internet, there a