skb web2.0

CS3352 Information Retrieval, Hypermedia and the Web 1

Web 2.0

Sean BechhoferSchool of Computer Science,

University of Manchester, UK

CS3352

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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?


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?


flickr

Google Maps

blogging

folksonomy

RSS

Wikis

WikipediaBitTorrent

Web ServicesCollective Intelligence

tagging

del.icio.us

What is Web 2.0?

mashups

AJAX

the long tailrich user experiences

micro-pagesservices not software

participation not publishing

emergence

ebay

skype


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.


Tim O’Reilly on Web 2.0• A recent essay by Tim O’Reilly sets out many of the

characteristics of Web 2.0.

• In the article, he describes seven principles of Web 2.0• Much of the following content will be based on these

observations.

What is Web 2.0 Design Patterns and Business Models for the Next Generation of Softwarehttp://www.oreillynet.com/pub/a/oreilly/tim/news/2005/09/30/what-is-web-20.html


[O’Reilly 05]


O’Reilly’s Principles1. Web as Platform

2. Harnessing Collective Intelligence

3. Data is the Next Intel Inside

4. End of the Software Release Cycle

5. Lightweight Programming Models

6. Software Above the Level of a Single Device

7. Rich User Experience


1. Web as Platform• Loosely Coupled Components • Bound together via web protocols and standards• Software as services

– Services as building blocks for other services


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


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.


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


The Intelligence LandscapeArtificial Intelligence

Lots

Not much

Not much

Lots

Collective Intelligence

Ontology Building Semantic

Web Services

FOAF

RSS

OWL

RDF

KnowledgeDiscovery

SWRL

Information linking

Social bookmarking

Flexible & extensible Metadataschemas

Decision making

Web

Sem

anti

cs


Evolution towards Read/Write WebWeb 2.0: Web pages plus other content, shared (interactively) over the web. More like an application than a page

Web 1.0: HTML pages served up then viewed using a browser

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


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.


Folksonomies

• 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)

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.


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


RSS

• Really Simple Syndication• Lightweight standard• Allows publication of content feeds

– Linking to resources, with notifications of page changes.

– Dynamic linking

– Pub/Sub

“The most significant advance in the fundamental architecture of the web since […] CGI.”

O’Reilly


<?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/[email protected]?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>[email protected] (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>


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)


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).


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.


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


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


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


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


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/


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.


AJAX

[Garrett 05]


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.


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.


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?


Next Week• Revision clinic with Carole on the 12th.• Keep an eye on the newsgroup for any further announcements!

skb web2.0

Technology

readwrite web web

principles of web

web protocols

thecharacteristics of

semantic web technology

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oreillys principles

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