Transcript WEB-2_en_3

WEB 2.0
What we are speaking about…
• Transformation of WEB, the WEB 2.0
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New generation of websites…
Importance of Open Data…
Importance of Users…
Web as application platform…
Web 2.0 hard to define…
• Web technolologies
– Client and server, HTTP, HTML, CSS
– Static and Dinamic web pages
• Web 2.0 technologies
– RSS, AJAX and the others…
Have you heard about them?
• Some new websites was born in the last
couple of years. They are
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„somehow different”
„not just plain” websites but services
giving a „Rich User Experience”
Wikipedia, Del.icio.us, Facebook, Google
services (Mail, Maps, Docs), Youtube,
Flickr, and more and more others, probably
you have heard about them…
Web 1.0  Web 2.0
Tendencies
• Britannica Online --> Wikipedia
• personal websites --> blogging
• publishing --> participation
• content management systems --> wikis
• directories (taxonomy) --> tagging ("folksonomy")
• mp3.com --> BitTorrent
• Screen scraping --> web services
• Stickiness --> syndication
Websites as Applications
• Rich Internet Applications – more than a
book or a computer program.
• Rich User Experience
• Instead a desktop PC program you can use
Internet services for your daily work (text
and image editing, watching movies)
• You can access your data and programs from
everywhere of the world.
• A Web 2.0 as platform
Participating
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Create not just consume
Community
Living on the web…
Social networking
User Ranking
Tagging
Blogging
Tagging example
Flickr.com
Open Data
• Open standards (w3c.org) to obey =
understandable content for everybody
• Data ownership
– Don’t steal my data, dont lock me in
• New copyright regulations (?)
• Content independent from the way of
visualization and the place of creation
• „No more secret”
© Tim O'Reilly
Web technologies – Client and server
Client
Client
Server
Client
Client
Basic Communication of WEB
Browser
(the client)
HTTP
req.
HTTP
ans.
Web
server
HTML
Web communication – Static Web
Browser
(the client)
HTTP
req.
HTTP
ans.
Web
Server
File system
static files
HTML, JPG, …
HTML
Web communication – Dynamic Web
Browser
(client)
HTTP
req.
HTTP
ans.
Web server
program
File system:
programs also
Pl. PHP
HTML
SQL req.
DATA
Database
server
Technologies: RSS
Really Simple Syndication (RSS 2.0)
Technologies: AJAX
Asynchronous JavaScript and XML
• It’s not ONE (new) technology, but more
technlolgies together:
– XHTML és CSS (to visualize the standardised
content);
– Document Object Model (Dinamic view and
interacivity)
– XML és XSLT; (Data transfer and data handling)
– XMLHttpRequest;
– JavaScript, the glue…
Ajax solves… (?)
• A Web is good to display html but can it be
used as a program? Interactivity?
• What do you do while the webserver creating
the page to your request? Waiting?
• Do you have to see when the browser makes a
connection to the server?
Differences - Modell
Differences - Communication
Who uses AJAX?
• „Paractical” examples (not in a „laboratory”):
– Google services (Gmail, Google Groups, Google
Maps, BodyBrowser, Picasa…)
– Google Documents – text editor, office programs
– Flickr – photos
– del.icio.us - bookmark
– Youtube – media
– Facebook – social
– Wikipedia