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= A bit of history: the Wold Wide Web =
==The Internet==


== WWW (what ?)==
==ARPANET: the first computer network==
HTML developed from the creation of the Wold Wide Web.


:Wold Wide Web, AKA www, AKA the Web, '''is not''' the Internet.
== Context for the creation of the ARPANET ==
* USA, 1960s
* Cold War
* Soviet Union launched in 1957 Sputnik - the first satellite
* Sputnik trigger a space race between US and the Soviet Union; the US only only change to win was to invest in scientific development
* ARPANET was created by the Advanced Research Projects Agency (ARPA) 


The Internet is essentially the motorway where many vehicles (or protocols) circulate, the Web is simply one of them. Others vehicles on the Internet are email, FTP, torrents, IRC chat, etc.
==Aims for the ARPANET==
* create access to remote computers
* allow a variety of computers to join the network and be accessed
* foster collaborative scientific research
* withstanding communications if faced with a nuclear attack
==Characteristics of the ARPANET==
* Distributed network: each node connects to more than 1 other node
** destruction of a node would not interrupt communication


The Web is a network of interlinked pages, that are accessible through a Web Browser. 
[[File:Brand-networks-topologies.jpg|3 network topologies|460px]]


http://i3.cpcache.com/product/1038181991/www_lets_share_what_we_know_canvas_lunch_bag.jpg
[[File:ARPANET-nodes-1971.jpg|ARPANET nodes 1971]]


==Tim Berners-Lee==
==Killer App: Email==
The vision for what would become the Web came from '''Tim Berners-Lee''' who happened to be working at CERN in the late 1980s
* At first the network was not heavily used
* It was difficult to access and use the different computers on the network
* the creation of electronic mail, brought many more users to network, which were simply using it to communicate
* the network changed from a resource sharing system to '''a communication system'''.


[[File:tim-berners-lee.jpg|Tim-Berners Lee]]
==Internet: the network that connected networks==
* by 1980 several digital networks, were functioning, besides ARPANET both in US and Europe:
** USENET, BITNET, FidoNet (Bulletin Board Network), etc
* these were isolated networks, not connected interconnected. 
* the task was to connect this networks
* to the wide and integrated network was given the name Internet
 
Listen to a radio program on Bulletin Board Networks: [http://www.npr.org/templates/story/story.php?storyId=120649723|The 'Wild And Woolly' World Of Bulletin Boards]


Documentary "World Brain" <ref>Degoutin, Stéphane, and Gwenola Wagon. World Brain Stéphane Degoutin & Gwenola Wagon, 2012. http://worldbrain.arte.tv.</ref>


== a bloody mess at CERN ==
Tim Berners-Lee in 1980 worked as a software developer at CERN.


He was faced with a few facts that would make him muse about what would later become the Web.


* CERN's incredible abundance of knowledge and research
* CERN's equally abundance of different computer hardware/software, protocols, file formats, documentation systems
'''<nowiki>==</nowiki> a bloody mess'''


== a unified, global '''documentation system'''==
-----
Berners-Lee wanted to create a unified, global '''documentation system''', that allowed CERN researchers to document and share their progress in both an easily readable easily writable way.


== Enquire ==
==The World Wide Web==
Berners-Lee's first efforts went to the development of a program called ENQUIRE, a pet project to help him remember the connections among the various people, computers and projects at CERN.
A world wide documentation system, sometimes known as the Web, same times as WWW


"In Enquire I could type in a page of information about a person, a device or a program. Each page was a ‘node’ in the program, a little like an index card. The only way to create a new node was to make '''a link''' from and old node"
==Context of Web's creation==
* conceptualized by Tim Berners-Lee at CERN
* Berners-Lee was frustrated with the difficulty circulation of information inside CERN
** diversity of computers with different systems
** large number of projects and individuals
** large amounts of information with no common system to organize and communicate this information


== a single information space ==
The Enquire experiment got him thinking:


"''Suppose all the information stored in computers everywhere were linked … Suppose I could program my computer to create '''a space in which anything could be linked to anything'''.'' All the bits of information in every computer at CERN, and on the planet, would be available to me and anyone else. These would be a single information space".
[[File:tim-berners-lee.jpg|Tim-Berners Lee]]


== Proposal ==
http://cache.boston.com/universal/site_graphics/blogs/bigpicture/lhc_08_01/lhc11.jpg
In a proposal written to CERN's administration Berner-Lee listed the '''requirements''' for this global information space:
* accessible across networks - providing data to different computers
* distributed - allowing anyone to write information
* non hierarchical - no tree structures, but stuff connected to stuff.


http://info.cern.ch/images/proposal.gif
Inside one of CERN's experiments.  [http://www.boston.com/bigpicture/2008/08/the_large_hadron_collider.html Source]
http://info.cern.ch/Proposal.html


== Hypertext ==
==Aim: find information==
Provided an non hierarchical way of connecting pieces of information, by interlinking them, and resulting in a web of content.
Tim Berners-Lee wanted to create a system that would:
* give access to files in different computers around the world.
* link the files among themselves
* facilitate the location and retrieval of information  


Berner-Lee recognized the similarities between his concept for a single information space and the web like structure that hypertext allowed.
"''Suppose all the information stored in computers everywhere were linked … Suppose I could program my computer to create '''a space in which anything could be linked to anything'''.'' All the bits of information in every computer at CERN, and on the planet, would be available to me and anyone else. These would be a single information space". <ref>Berners-Lee, Tim. Weaving the Web. London: TEXERE, 2000.</ref>


== HTML ==
==How==
To put his ideas into practice Berner-Lee turned into one of the available '''markup languages''', SGML.
Tim Berners-Lee  
[[File:OED-LEXX-Bungler.jpg|A snipped of SGML]]
* devised a system that connected information through '''links''' (hypertext)
* created a '''hyper text language''': '''HTML''' (Hyper Text Markup Language)
* wrote an '''interpreter for HTML''' (that transforms HTML code into visual form): a '''web browser''' <ref>[http://line-mode.cern.ch/www/hypertext/WWW/TheProject.html Simulation of the first Web Browser]</ref>
* implemented a systems of addresses - URL - that allowed files in remote computers to be called and reply by sending back a (usually) HTML file.


He simplified, and added '''external hyperlink''', to allow connection to external documents (in one direction).
==Result==
<source lang="html4strict">
* The Web became a system where information was easier to find
<!DOCTYPE html>
* users of host computers (servers) could easily decide what they said to the world, and also change it
<html>
* users became publishers of content on the Web (not even needing access to a server in order to do it)
  <head>
* that publishing possibility and will triggered the creation of web publishing services and formats (Geocities, blogs, Tumblrs, Facebook walls ,etc)
    <title>Hello World</title>
* in this context the user is not only a consumer, but also a producer of content (or publisher)
  </head>
  <body>
    <h1>Greetings</h1>
    <p>This is my homepage!</p>
  </body>
</html>
</source>


The marking is done by enclosing content in the element that will format it <nowiki><element>content</element></nowiki>
----
-------


==  Editor, Browser, Go ==
==  Editor, Browser, Go ==
* Editor - your html writing tool
* Editor - your HTML writing tool
* Browser - the interpreter of html, but also a debug and prototyping space
* Browser - the interpreter of HTML, but also a debug and prototyping space. (Read about what goes on behind the scenes in a Web browser <ref>“Introduction to HTML” https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Introduction.</ref>)




== html essential structural elements==
==HTML==
* doctype <code><!DOCTYPE html></code> - an indication to the browser of what content will be given to it to interpret
* HTML is a markup language
* html - all the content of an html file
* meaning: content is marked with different "values"; e.g: paragraph, bold, italic, heading title, etc
* head - mostly invisible content: page title, character encoding, styles, etc. (not essential)
* marking is done through tags that wrap the content  
* body - mostly visible content  


== golden rules ==
http://publicationstation.wdka.hro.nl/go/kickoff/imgs/html.gif
Once open a tag must be closed, either with


* an end tag: '''<code></h1></code>'''
* In order to '''format content with tags''' you need to enter the content between an opening and closing element. As in the following case:
<code lang="html4strict">
<nowiki><h1>My Title</h1></nowiki>
<h1>Closing Heading 1</h1>
** <nowiki><h1></nowiki> is the opening tag
</code>
** <nowiki></h1></nowiki> is the closing tag


* self-closing tag: '''<code><hr /></code>'''
* at times you'll find '''self-closing tags''' which have no content inside them, like horizontal rulers '''<code><hr /></code>'''
<code lang="html4strict">
or line breaks <nowiki><br/></nowiki>
<img src="nice_picture.jpg" />
</code>




== essential tags ==
== essential HTML tags ==
<pre>
<pre>
Comments: <!-- comments -->
Title Headers: <h1>,<h2>,<h3>,<h4>
Header: <h1>,<h2>,<h3>,<h4>
Paragraph: <p>
Paragraph: <p>
Line break: <br />
Line break: <br />
italics: <i>
italics: <i>
bold: <b>
bold: <b>
lists: <ul> or <ol>
list items: <li>


div container: <div>
Comments: <!-- comments -->
span: <span>


Hyperlink(requires arguments): <a href="http://thecolourclock.co.uk/">a link</a></code>
</pre>
Image(requires arguments): img src="nice_picture.jpg" />
 
 
== HTML skeleton ==
The previous tags only provided content formatting, yet '''to create any working web-page we need to always place the content inside a ''HTML page skeleton'''''.


</pre>
[[File:skeleton.svg]]
 
 
 
 
==HTML element reference==
HTML element reference provides information and examples on every HTML element
 
https://developer.mozilla.org/en-US/docs/Web/HTML/Element
 
==<nowiki><a></nowiki> anchor tag - hyperlinks==
<source lang="html4strict">
<a href="http://www.worm.org/">Worm website</a>
<br/>
<a href="http://tentrotterdam.nl/">tentrotterdam.nl</a>
</source>
 
* the href (address) of a link has to be a complete URL: beginning with http or https
 
==remote links==
Normally, like in the example above, you use links to point users to other sites.
 
Those are '''remote links'''
 
==local links==
Also usually you use '''local links'''.
 
Those are links to other files/pages you have create.
 
They allow to move within your website.
 
<source lang="html4strict">
Go to next <a href="next.html">Next</a> page.
</source>
 
 
==<code><img></code> image tag==
<source lang="html4strict">
<img src="http://data.whicdn.com/images/106829085/large.gif" />
<br/>
<img src="my-img.jpg" />
</source>
 
 
==Local file paths==
Local links and image are some times in parent or child folders, different from the folder of your webpage.
 
To get an image to load or link to land on the right file, you have to '''indicate the correct path to them'''.
 
[[File:folder_structure.svg]]
 
 
==Local file paths exercise==
* Create an HTML file, that uses other local images and links to other local html files.
* Move the HTML file to a different folder.
* Keep images and linked pages in the fold they were it.
* Try to make all the local files are '''not broken'''  in HTML file
 
== <nowiki><div></nowiki> div tag ==
The div tag is essentially a container of other content.
<source lang="html4strict">
<div style="background:black; color:red; width:400px">                     
    <h1>Beautiful page</h1>                                                   
    <p>writing stuff                                                           
      <i>inside</i>                                                            
    </p>                                                                       
</div>
</source>
== <nowiki><span></nowiki> span tag==
The span tag is like a color marker on text
<source lang="html4strict">
<p>A magazine that offers a platform for
  <span style="background:red; color:blue; font-size:40px">challenging and engaging</span>
design and art practices</p>
</source>
 
style it is an attribute
 
==tags' attributes==
attributes are parameters that modify the HTML tags behavior
 
==<nowiki><a></nowiki> attributes:==
<source lang="html4strict">
<a href="http://wdka.hro.nl/" target="_self">link</a> <!-- target="_self": Loads the response into the SAME tab-->                 
<br/>                                                                                                                                   
<a href="http://wdka.hro.nl/" target="_blank">link</a> <!-- target="_blank": Loads the response into a NEW tab-->       
</source>
* href: url or file of the link
* target: where (in what window) to display the linked file. 
 
==<code><img></code> attributes:==
<source lang="html4strict">
<img src="http://www.wdka.nl/wp-content/uploads/sites/4/2015/01/Project-Show_I1.jpeg" title="my pic" height="100px" width="200px"/>
</source>
* src: location of the image
* title: title of the image
* width
* height
 
==inspector==
 
== Optional Reading ==
Stephenson, Neal. “Mother Earth Mother Board.” Wired, http://archive.wired.com/wired/archive/4.12/ffglass_pr.html.
 
Abbate, Janet. Inventing the Internet. MIT Press, 2000.
 
==References, Notes and Optional Reading ==


----
<references />


== Resources ==
“The Birth of the Web,”  http://home.web.cern.ch/topics/birth-web .
Historical:
http://home.web.cern.ch/topics/birth-web - on the birth of the Web at CERN from CERN


Technical:
==Technical Resources ==
* https://developer.mozilla.org/en-US/docs/Web/HTML - HTML (HyperText Markup Language)
* https://developer.mozilla.org/en-US/docs/Web/HTML - HTML (HyperText Markup Language)
* https://developer.mozilla.org/en-US/docs/Web/HTML/Element - HTML element reference
* https://developer.mozilla.org/en-US/docs/Web/HTML/Element - HTML element reference
* http://diveintohtml5.info - HTML 5

Revision as of 20:22, 4 October 2015

<slidy theme="aa"/>

The Internet

ARPANET: the first computer network

Context for the creation of the ARPANET

  • USA, 1960s
  • Cold War
  • Soviet Union launched in 1957 Sputnik - the first satellite
  • Sputnik trigger a space race between US and the Soviet Union; the US only only change to win was to invest in scientific development
  • ARPANET was created by the Advanced Research Projects Agency (ARPA)

Aims for the ARPANET

  • create access to remote computers
  • allow a variety of computers to join the network and be accessed
  • foster collaborative scientific research
  • withstanding communications if faced with a nuclear attack

Characteristics of the ARPANET

  • Distributed network: each node connects to more than 1 other node
    • destruction of a node would not interrupt communication

3 network topologies

ARPANET nodes 1971

Killer App: Email

  • At first the network was not heavily used
  • It was difficult to access and use the different computers on the network
  • the creation of electronic mail, brought many more users to network, which were simply using it to communicate
  • the network changed from a resource sharing system to a communication system.

Internet: the network that connected networks

  • by 1980 several digital networks, were functioning, besides ARPANET both in US and Europe:
    • USENET, BITNET, FidoNet (Bulletin Board Network), etc
  • these were isolated networks, not connected interconnected.
  • the task was to connect this networks
  • to the wide and integrated network was given the name Internet

Listen to a radio program on Bulletin Board Networks: 'Wild And Woolly' World Of Bulletin Boards

Documentary "World Brain" [1]




The World Wide Web

A world wide documentation system, sometimes known as the Web, same times as WWW

Context of Web's creation

  • conceptualized by Tim Berners-Lee at CERN
  • Berners-Lee was frustrated with the difficulty circulation of information inside CERN
    • diversity of computers with different systems
    • large number of projects and individuals
    • large amounts of information with no common system to organize and communicate this information


Tim-Berners Lee

lhc11.jpg

Inside one of CERN's experiments. Source

Aim: find information

Tim Berners-Lee wanted to create a system that would:

  • give access to files in different computers around the world.
  • link the files among themselves
  • facilitate the location and retrieval of information

"Suppose all the information stored in computers everywhere were linked … Suppose I could program my computer to create a space in which anything could be linked to anything. All the bits of information in every computer at CERN, and on the planet, would be available to me and anyone else. These would be a single information space". [2]

How

Tim Berners-Lee

  • devised a system that connected information through links (hypertext)
  • created a hyper text language: HTML (Hyper Text Markup Language)
  • wrote an interpreter for HTML (that transforms HTML code into visual form): a web browser [3]
  • implemented a systems of addresses - URL - that allowed files in remote computers to be called and reply by sending back a (usually) HTML file.

Result

  • The Web became a system where information was easier to find
  • users of host computers (servers) could easily decide what they said to the world, and also change it
  • users became publishers of content on the Web (not even needing access to a server in order to do it)
  • that publishing possibility and will triggered the creation of web publishing services and formats (Geocities, blogs, Tumblrs, Facebook walls ,etc)
  • in this context the user is not only a consumer, but also a producer of content (or publisher)

Editor, Browser, Go

  • Editor - your HTML writing tool
  • Browser - the interpreter of HTML, but also a debug and prototyping space. (Read about what goes on behind the scenes in a Web browser [4])


HTML

  • HTML is a markup language
  • meaning: content is marked with different "values"; e.g: paragraph, bold, italic, heading title, etc
  • marking is done through tags that wrap the content

html.gif

  • In order to format content with tags you need to enter the content between an opening and closing element. As in the following case:

<h1>My Title</h1>

    • <h1> is the opening tag
    • </h1> is the closing tag
  • at times you'll find self-closing tags which have no content inside them, like horizontal rulers

or line breaks <br/>


essential HTML tags

Title Headers: <h1>,<h2>,<h3>,<h4>
Paragraph: <p>
Line break: <br />
italics: <i>
bold: <b>

Comments: <!-- comments -->


HTML skeleton

The previous tags only provided content formatting, yet to create any working web-page we need to always place the content inside a HTML page skeleton.

Skeleton.svg



HTML element reference

HTML element reference provides information and examples on every HTML element

https://developer.mozilla.org/en-US/docs/Web/HTML/Element

<a> anchor tag - hyperlinks

<a href="http://www.worm.org/">Worm website</a>
<br/>
<a href="http://tentrotterdam.nl/">tentrotterdam.nl</a>
  • the href (address) of a link has to be a complete URL: beginning with http or https

remote links

Normally, like in the example above, you use links to point users to other sites.

Those are remote links

local links

Also usually you use local links.

Those are links to other files/pages you have create.

They allow to move within your website.

Go to next <a href="next.html">Next</a> page.


image tag

<img src="http://data.whicdn.com/images/106829085/large.gif" />
<br/>
<img src="my-img.jpg" />


Local file paths

Local links and image are some times in parent or child folders, different from the folder of your webpage.

To get an image to load or link to land on the right file, you have to indicate the correct path to them.

Folder structure.svg


Local file paths exercise

  • Create an HTML file, that uses other local images and links to other local html files.
  • Move the HTML file to a different folder.
  • Keep images and linked pages in the fold they were it.
  • Try to make all the local files are not broken in HTML file

<div> div tag

The div tag is essentially a container of other content.

<div style="background:black; color:red; width:400px">                      
    <h1>Beautiful page</h1>                                                     
    <p>writing stuff                                                            
      <i>inside</i>                                                             
    </p>                                                                        
</div>

<span> span tag

The span tag is like a color marker on text

<p>A magazine that offers a platform for 
   <span style="background:red; color:blue; font-size:40px">challenging and engaging</span> 
design and art practices</p>

style it is an attribute

tags' attributes

attributes are parameters that modify the HTML tags behavior

<a> attributes:

<a href="http://wdka.hro.nl/" target="_self">link</a> <!-- target="_self": Loads the response into the SAME tab-->                  
<br/>                                                                                                                                    
<a href="http://wdka.hro.nl/" target="_blank">link</a> <!-- target="_blank": Loads the response into a NEW tab-->
  • href: url or file of the link
  • target: where (in what window) to display the linked file.

attributes:

<img src="http://www.wdka.nl/wp-content/uploads/sites/4/2015/01/Project-Show_I1.jpeg" title="my pic" height="100px" width="200px"/>
  • src: location of the image
  • title: title of the image
  • width
  • height

inspector

Optional Reading

Stephenson, Neal. “Mother Earth Mother Board.” Wired, http://archive.wired.com/wired/archive/4.12/ffglass_pr.html.

Abbate, Janet. Inventing the Internet. MIT Press, 2000.

References, Notes and Optional Reading

  1. Degoutin, Stéphane, and Gwenola Wagon. World Brain Stéphane Degoutin & Gwenola Wagon, 2012. http://worldbrain.arte.tv.
  2. Berners-Lee, Tim. Weaving the Web. London: TEXERE, 2000.
  3. Simulation of the first Web Browser
  4. “Introduction to HTML” https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Introduction.

“The Birth of the Web,” http://home.web.cern.ch/topics/birth-web .

Technical Resources