The document discusses the key concepts of Web 2.0, including how it utilizes collective intelligence through social bookmarking, tagging, wikis and collaborative filtering. It also examines how Web 2.0 applications harness the network effect to aggregate user data and benefit from increased participation. Finally, it outlines some of the design principles of Web 2.0 such as treating the web as a platform, harnessing collective intelligence, and providing rich user experiences through technologies like AJAX.

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Sean Bechhofer
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CS3352
CS3352 Information Retrieval, Hypermedia and the Web 1

2. Things to think about
• How would we use Semantic Web technology to help us build
Web 2.0 applications?
• How would I change my information delivery mechanisms to
make my data/content more amenable to Web 2.0?
CS3352 Information Retrieval, Hypermedia and the Web 2

3. Web 2.0
• What was Web 1.0?
• What is Web 2.0?
• Is it the same as Semantic Web?
– If not, is it better than Semantic Web?
• Is it Web Services?
– If not, is it better than Web Services?
• How will we do it?
– What are the technologies/methodologies?
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4. What is Web 2.0?
flickr tagging
Wikis
skype
participation not publishing
Web Services
blogging
micro-pages Collective Intelligence
del.icio.us
folksonomy services not software
Google Maps
ebay AJAX RSS
Wikipedia
BitTorrent emergence
mashups
the long tail
rich user experiences
CS3352 Information Retrieval, Hypermedia and the Web 4

5. What is Web 2.0?
• “Web 2.0” is a term used to describe an emerging collections of
technologies, approaches and principles.
– Perhaps already somewhat overused and hyped
• What is it that allows us to identify and characterise an
application or an approach as Web 2.0?
– The answer to this is not cut and dried. Applications and companies
claiming to be Web 2.0 are not, while others that make no claim
are.
CS3352 Information Retrieval, Hypermedia and the Web 5

6. Tim O’Reilly on Web 2.0
• A recent essay by Tim O’Reilly sets out many of the
characteristics of Web 2.0.
What is Web 2.0 Design Patterns and Business Models for
the Next Generation of Software
http://www.oreillynet.com/pub/a/oreilly/tim/news/2005/09/30/what-is-web-20.html
• In the article, he describes seven principles of Web 2.0
• Much of the following content will be based on these
observations.
CS3352 Information Retrieval, Hypermedia and the Web 6

7. [O’Reilly 05]
CS3352 Information Retrieval, Hypermedia and the Web 7

8. O’Reilly’s Principles
• Web as Platform
• Harnessing Collective Intelligence
• Data is the Next Intel Inside
• End of the Software Release Cycle
• Lightweight Programming Models
• Software Above the Level of a Single Device
• Rich User Experience
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9. 1. Web as Platform
• Loosely Coupled Components
• Bound together via web protocols and standards
• Software as services
– Services as building blocks for other services
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10. 2. Harnessing Collective Intelligence
• Successful Web 2.0 applications make use of, and exploit the
notions of collective intelligence
– Social Bookmarking
– Tagging
– Wikis
– “If you liked that, you’ll like this”
• Collaborative filtering
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11. The Network Effect
• Goods or services that increase in value depending on the
number of people owning or using that service.
• E.g. Telephones
– If there are only two people in the world with telephones, the
telephone is not that useful.
– If there are 1 billion telephones, then the telephone is useful.
• Similarly for sites such as eBay.
– More buyers leads to more competition for items and higher prices.
– Higher prices attracts sellers, introduces competition and drives
prices down.
• Social networking sites (e.g. LinkedIn)
– The more people using the site, the more useful it becomes.
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12. Network Effects
• Getting information or value into applications can be hard
– Pay people
– Get volunteers
– ???
• Make it as easy as possible to aggregate user data as a side-
effect of them using your application
• E.g. flickr
– Photos, tags etc. default to public
• Network Effects by Default
– O’Reilly design principle
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13. The Intelligence Landscape
Artificial Intelligence
Decision making
OWL
Lots SWRL Knowledge
Discovery
Ontology
Semantics
Building Semantic Information linking
Web
Services
Flexible &
RDF FOAF
Not extensible Social
much Metadata bookmarking
RSS
schemas
Collective Intelligence
Not
Lots
much Web
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14. Evolution towards Read/Write Web
Web 1.0: HTML pages Web 2.0: Web pages plus other
served up then viewed content, shared (interactively) over
using a browser the web. More like an application
than a page
Read £ Write & Contribute
Page £ Post
Static £ Dynamic
Web Browser £ Browser, RSS Reader, App
Client/Server £ Web Services
Web Coders £ Everyone
Geeks £ Mass Amateurisation
Consumer as Producer
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15. Wikis
• Simple, collaborative mechanism for building and maintaining
web pages.
• Wikipedia perhaps the best known example
• But…
– Needs some organisational structure
– May also need editorial control
– “Just who would want to vandalise an entry on cheese?”
• Semantic Wikis
– Using SW technologies to help
organise and search through wiki
contents.
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16. Folksonomies
A collaborative but unsophisticated way in which
information is being categorized on the web. Instead of
using a centralized form of classification, users are
encouraged to assign freely chosen keywords (called tags)
to pieces of information or data, a process known as
tagging.
• Used in sites like flickr or del.icio.us and in general in social
networking applications
• Provide an unrestricted way of building a vocabulary.
– Lightweight, quick and easy
– Little constraint on users (thus popular)
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17. Folksonomies
• Folksonomies may provide a nice quick way to produce
lightweight, flat collections of keywords, but are less likely to
help produce detailed ontologies.
• Ok if you’re browsing (e.g. photo libraries), but what about
directed searching?
• Tom Gruber’s “ontology of folksonomy”
– http://tomgruber.org/writing/ontology-of-folksonomy.htm
– Introducing some structure to the tagging process
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18. RSS
“The most significant advance in the fundamental
architecture of the web since […] CGI.”
O’Reilly
• Really Simple Syndication
• Lightweight standard
• Allows publication of content feeds
– Linking to resources, with notifications of page changes.
– Dynamic linking
– Pub/Sub
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19. <?xml version="1.0" encoding="utf-8"?>
<rss version="2.0" xmlns:media="http://search.yahoo.com/mrss">
<channel>
<title>guitarfish's Photos</title>
<link>http://www.flickr.com/photos/guitarfish/</link>
<description>A feed of guitarfish's Photos</description>
<pubDate>Thu, 27 Apr 2006 10:04:51 -0800</pubDate>
<lastBuildDate>Thu, 27 Apr 2006 10:04:51 -0800</lastBuildDate>
<generator>http://www.flickr.com/</generator>
<image>
<url>http://static.flickr.com/49/buddyicons/66243365@N00.jpg?1145894649</url>
<title>guitarfish's Photos</title>
<link>http://www.flickr.com/photos/guitarfish/</link>
</image>
<item>
<title>Drink Beer!</title>
<link>http://www.flickr.com/photos/guitarfish/135976102/</link>
<description>guitarfish posted a photo:...</description>
<pubDate>Thu, 27 Apr 2006 10:04:51 -0800</pubDate>
<author>nobody@flickr.com (guitarfish)</author>
<guid isPermaLink="false">tag:flickr.com,2004:/photo/135976102</guid>
<media:content url="http://static.flickr.com/50/135976102_b29b452f0a_o.jpg"
type="image/jpeg"
height="576"
width="768"/>
<media:title>Drink Beer!</media:title>
<media:text type="html">...</media:text>
<media:thumbnail url="http://static.flickr.com/50/135976102_b29b452f0a_s.jpg" height="75" width="75"/>
<media:credit role="photographer">guitarfish</media:credit>
<media:category scheme="urn:flickr:tags">beer japan</media:category>
</item>
<item>…</item>
</channel>
</rss>
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20. RSS
• RSS feeds describe items
– Title, Description, Link, Publication date etc.
• RSS aggregation originally through web-browser.
• Now a wide variety of applications
– Web Browser
– Desktop
– Mobile Device
• Alternatives exists, e.g. Atom, TPEG (Transport Protocol
Experts Group)
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21. Feeds
• Feeds now supply a huge variety of content and data updates:
– Stock quotes
– Weather data
– TV and Radio schedules
– Travel information
• See, for example the BBC’s backstage initiative:
– http://backstage.bbc.co.uk/
– Content feeds provided for developers to build novel applications
based on BBC content (see Mashups).
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22. 3. Data is the next Intel Inside
• Successful Internet applications have been backed by
specialised databases
– Google, Amazon, Yahoo!, eBay, Napster
• Who owns this data?
• Without ownership, it’s easy for competitors to enter the market
and offer competing applications simply by licensing the same
data.
– E.g. MapQuest quickly overtaken by Yahoo!, Microsoft and now
Google.
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23. Enhanced Data
• Amazon took original ISBN database and enhanced it
• Information from publishers
• Information from users (reviews, comments etc)
– Relies on it being easy to add value to the users
– Cf. Network Effects
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24. 4. End of the Software Release
Cycle
• Web 2.0 software is delivered as services, not as a product.
• Maintenance becomes crucial
– Refining services
– Google continually updating/crawling
• Users as co-developers
– Open Source philosophies
– Release early, release often
– Collective debugging
– Close monitoring of features.
• Participation
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25. 5. Lightweight Programming
• Loosely coupled systems
– Web Services (cf. Mark Little’s lecture)
– Moving away from heavyweight APIs: CORBA, RMI etc.
– Implementation independence
• Syndication rather than coordination
– Pushing data out
– Don’t care what then happens
• Reuse and Remix
– Creating novel applications through assembly
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26. Mashups
• Applications that take information from multiple sources and
merge it, providing added value
• Many mashups make use of the Google Maps API or Google
Earth
– Combining BBC Travel feeds with Google Maps to show real time
traffic problems
• http://bbc.blueghost.co.uk
– Geographical locations featuring on TV:
• http://tvmap.thomasscott.net/
– Good news/Bad news classification
• http://www.latedecember.com/sites/moodnews/index.html
– Overlaying multiple sites onto Google Maps,
• http://www.dynamite.co.uk/local/
– Flickr Sudoku!
• http://flickrsudoku.com/default.aspx
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27. Mashups
• Key here is content/data provided via services
– Not just screen scraping
• What about metadata?
– Lots of different data
• Geographical locations
• Descriptions
• Tags
• Authors
– How do I know what this stuff is all about?
– How do I know which things I should be combining?
• 2.75 new mashups every day
– http://www.mashupfeed.com/
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28. 7. Rich User Experience
• JavaScript and DHTML provided rich client side programming in
a lightweight fashion.
• AJAX (Asynchronous Javascript + XML)
– Term coined by Jesse James Garrett of Adaptive Path
– Standards-based presentation using XHTML and CSS;
– Dynamic display and interaction using the Document Object Model;
– Data interchange and manipulation using XML and XSLT;
– Asynchronous data retrieval using XMLHttpRequest;
– JavaScript binding everything together.
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29. AJAX
[Garrett 05]
CS3352 Information Retrieval, Hypermedia and the Web 29

30. AJAX
• AJAX engine takes care of interaction with the server and
rendering content for the user.
– Asynchronous communication with the server
– No waiting for pages to load
– Smoother User Experience
• Examples
– Google Suggest
• Providing suggestions as you type.
– Google Maps
• Pan, Zoom, Expand
– flickr
• Move away from Flash to AJAX-based implementations
• Open and standards based.
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31. Friend or Foe?
• Web 2.0, Semantic Web and
Web Services should not be seen
as competing technologies or
approaches.
• Rather they are complementary
• Web Services are key to delivering
information and services in a loosely coupled way, and allow
flexible repurposing of content.
• Semantics (both rich and lightweight) are needed to describe
our resources in order to facilitate reuse.
CS3352 Information Retrieval, Hypermedia and the Web 31

32. Things to think about (reprise)
• How would we use Semantic Web technology to help us build
Web 2.0 applications?
• How would I change my information delivery mechanisms to
make my data/content more amenable to Web 2.0?
CS3352 Information Retrieval, Hypermedia and the Web 32

33. Next Week
• Revision clinic with Carole on the 12th.
• Keep an eye on the newsgroup for any further announcements!
CS3352 Information Retrieval, Hypermedia and the Web 33

34. Benefits to People
• Collective intelligence - collaborative
• Transparent - instant gratification
• Non-hierarchical - democratic
• Potential for passion - ownership
• Open to public - real recognition
• Permanence - searchable resource
CS3352 Information Retrieval, Hypermedia and the Web 34

35. Web 2.0 Design Patterns
• The Long Tail
• Data is the Next Intel Inside
• Users add Value
• Network Effects by Default
• Some Rights Reserved
• The Perpetual Beta
• Cooperate, Don’t Control
• Software Above the Level of a Single Device
CS3352 Information Retrieval, Hypermedia and the Web 35

36. Features for the Web 2.0 Enterprise
• Services, not packaged software, with cost-effective scalability
• Control over unique, hard-to-recreate data sources that get
richer as more people use them
• Trusting users as co-developers
• Harnessing collective intelligence
• Leveraging the long tail through customer self-service
• Software above the level of a single device
• Lightweight user interfaces, development models, AND
business models
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