Web 2.0
•Web 2.0, http://en.wikipedia.org/wiki/Web_2 (2007-3-6)
Background
• Web 2.0, a phrase coined by O'Reilly Media in 2004,[1] refers to a
perceived second-generation of Web-based services—such as social
networking sites, wikis, communication tools, and folksonomies—that
emphasize online collaboration and sharing among users.
• O'Reilly Media, in collaboration with MediaLive International, used the
phrase as a title for a series of conferences, and since 2004 some developers
and marketers have adopted the catch-phrase.
• Its exact meaning remains open to debate, and some technology experts,
notably Tim Berners-Lee[2], have questioned whether the term has
meaning.
• The last, compact definition of Web 2.0, according to Tim O'Reilly is this
one:
– "Web 2.0 is the business revolution in the computer industry caused by the
move to the internet as platform, and an attempt to understand the rules for
success on that new platform. Chief among those rules is this: Build
applications that harness network effects to get better the more people use
them."
Web 2.0
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Introduction
• The phrase "Web 2.0" hints at an improved form of the World Wide Web;
• Advocates suggest that technologies such as weblogs, social bookmarking,
wikis, podcasts, RSS feeds (and other forms of many-to-many publishing),
social software, Web APIs, Web standards and online Web services imply a
significant change in web usage.
• The phrase "Web 2.0" can also refer to one or more of the following:
– The transition of websites from isolated information silos to sources of content
and functionality, thus becoming computing platforms serving web applications
to end-users
– A social phenomenon embracing an approach to generating and distributing
Web content itself, characterized by open communication, decentralization of
authority, freedom to share and re-use, and "the market as a conversation"
– Enhanced organization and categorization of content, emphasizing deeplinking
– A rise or fall in the economic value of the Web, possibly surpassing the impact
of the dot-com boom of the late 1990s
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Introduction
• In the first Web 2.0 conference, Tim O'Reilly and John Battelle
summarized key principles of Web 2.0 applications:
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the web as a platform
data as the driving force
network effects created by an architecture of participation
innovation in assembly of systems and sites composed by pulling
together features from distributed, independent developers (a kind of
"open source" development)
lightweight business models enabled by content and service syndication
the end of the software adoption cycle ("the perpetual beta")
software above the level of a single device, leveraging the power of
The Long Tail.
easy to pick up by early adopters
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Introduction
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Tim O'Reilly gave examples of companies or products that embody these principles
in his description of his "four plus one" levels in the hierarchy of Web 2.0-ness: [5]
– Level 3 applications, the most "Web 2.0", which could only exist on the Internet, deriving
their power from the human connections and network effects Web 2.0 makes possible,
and growing in effectiveness the more people use them. O'Reilly gives as examples:
eBay, craigslist, Wikipedia, del.icio.us, Skype, dodgeball, and Adsense.
– Level 2 applications, which can operate offline but which gain advantages from going
online. O'Reilly cited Flickr, which benefits from its shared photo-database and from its
community-generated tag database.
– Level 1 applications, also available offline but which gain features online. O'Reilly
pointed to Writely (since 10 October 2006: Google Docs & Spreadsheets, offering groupediting capability online) and iTunes (because of its music-store portion).
– Level 0 applications would work as well offline. O'Reilly gave the examples of
MapQuest, Yahoo! Local, and Google Maps. Mapping applications using contributions
from users to advantage can rank as level 2.
– non-web applications like email, instant-messaging clients and the telephone.
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Time bar of Web 2.0 buzz words
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Web 1.0 vs. Web 2.0
Aplications
Web 1.0
Web 2.0
DoubleClick
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Google AdSense
Ofoto
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Flickr
Akamai
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BitTorrent
mp3.com
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Napster
Britannica Online
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Wikipedia
personal websites
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blogging
evite
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upcoming.org and EVDB
domain name speculation
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search engine optimization
page views
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cost per click
screen scraping
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web services
publishing
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participation
content management systems
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wikis
directories (taxonomy)
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tagging ("folksonomy")
stickiness
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syndication
Characteristics of "Web 2.0"
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While interested parties continue to debate the definition of a Web 2.0 application,
a Web 2.0 web-site may exhibit some basic characteristics. These might include:
– "Network as platform" — delivering (and allowing users to use) applications entirely
through a browser.[6] See also Web operating system.
– Users owning the data on the site and exercising control over that data.[7][6]
– An architecture of participation and democracy that encourages users to add value to the
application as they use it.[6][1] This is a sharp contrast to hierarchical access control in
applications, in which users are categorized into roles with varying levels of functionality.
– A rich, interactive, user-friendly interface based on Ajax[6][1] or similar frameworks.
– Some social-networking aspects.[7][6]
– a Public good. "public goods" are characterized by two properties: jointness of supply
and non-excludability (Hardin, 1982 [1]). The impossibility to exclude group members
who didn’t contribute to the provision of goods from sharing its profits gives rise to the
possibility that rational members will prefer to withhold their contribution of effort and
free ride on the contribution of others (Marwell and Ames, 1979 [2]; Web 2.0 as Public
Good [3]).
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The concept of Web-as-participation-platform captures many of these
characteristics. Bart Decrem, founder and former CEO of Flock calls Web 2.0 the
"participatory Web"[8] and regards Web-as-information-source as Web 1.0.
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Technology Overview
• A Web 2.0 website may typically feature a number of the following
techniques:
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Rich Internet application techniques, optionally Ajax-based
CSS
Semantically valid XHTML markup and the use of Microformats
Syndication and aggregation of data in RSS/Atom
Clean and meaningful URLs
Extensive use of folksonomies (in the form of tags or tagclouds, for example)
Use of wiki software either completely or partially (where partial use may grow
to become the complete platform for the site)
– Weblog publishing
– Mashups
– REST or XML Webservice APIs
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Innovations associated with "Web 2.0"
• Web-based applications and desktops
– The richer user-experience afforded by Ajax has prompted the development of
web-sites that mimic personal computer applications, such as word processing,
the spreadsheet, and slide-show presentation. WYSIWYG wiki sites replicate
many features of PC authoring applications. Still other sites perform
collaboration and project management functions. Java enables sites that provide
computationally intensive video capability. Google, Inc. acquired one of the
best-known sites of this broad class, Writely.
– Several browser-based "operating systems" or "online desktops" have also
appeared. They essentially function as application platforms, not as operating
systems per se. These services mimic the user experience of desktop operatingsystems, offering features and applications similar to a PC environment. They
have as their distinguishing characteristic the ability to run within any modern
browser.
– Numerous web based application services appeared during the dot-com bubble
of 1997–2001 and then vanished, having failed to gain a critical mass of
customers. In 2005 WebEx acquired one of the better-known of these,
Intranets.com, for slightly more than the total it had raised in venture capital
after six years of trading.
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Innovations associated with "Web 2.0"
• Rich Internet applications
– Main article: Rich Internet application
– Recently, rich-Internet application techniques such as Ajax, Adobe
Flash, Flex and OpenLaszlo have evolved that can improve the userexperience in browser-based applications. These technologies allow a
web-page to request an update for some part of its content, and to alter
that part in the browser, without needing to refresh the whole page at
the same time.
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Innovations associated with "Web 2.0"
• Server-side software
– The functionality of Web 2.0 rich Internet applications builds on the
existing Web server architecture, but puts much greater emphasis on
back-end software.
– Syndication differs only nominally from the methods of publishing
using dynamic content management, but web services typically require
much more robust database and workflow support, and become very
similar to the traditional intranet functionality of an application server.
– Vendor approaches to date fall under either a universal server approach,
which bundles most of the necessary functionality in a single server
platform, or a web-server plugin approach, which uses standard
publishing tools enhanced with API interfaces and other tools.
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Innovations associated with "Web 2.0"
• Client-side software
• The extra functionality provided by Web 2.0 depends on the
ability of users to work with the data stored on servers. This
can come about through forms in an HTML page, through a
scripting language such as Javascript, or through Flash or Java.
These methods all make use of the client computer to reduce
the server workloads.
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Innovations associated with "Web 2.0"
• RSS
– Main article: RSS (file format)
• The first and the most important step (according to one point of view) of
evolution towards Web 2.0 involves the syndication of site content, using
standardized protocols which permit end-users to make use of a site's data
in another context, ranging from another web-site, to a browser plugin, or
to a separate desktop application. Protocols which permit syndication
include RSS (Really Simple Syndication — also known as "web
syndication"), RDF (as in RSS 1.1), and Atom, all of them flavors of XML.
Specialized protocols such as FOAF and XFN (both for social networking)
extend functionality of sites or permit end-users to interact without
centralized web-sites. (See microformats for more specialized data formats.)
• Due to the recent development of these trends, many of these protocols
remain de facto (rather than formal) standards.
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Innovations associated with "Web 2.0"
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Web protocols
Web communication protocols provide a key element of the Web 2.0 infrastructure.
Major protocols include REST and SOAP.
REST (Representational State Transfer) indicates a way to access and manipulate
data on a server using the HTTP verbs GET, POST, PUT, and DELETE
SOAP involves POSTing XML messages and requests to a server that may contain
quite complex, but pre-defined, instructions for the server to follow
In both cases, an API defines access to the service. Often servers use proprietary
APIs, but standard web-service APIs (for example, for posting to a blog) have also
come into wide use. Most (but not all) communications with web services involve
some form of XML (eXtensible Markup Language).
See also Web Services Description Language (WSDL) (the standard way of
publishing a SOAP API) and the list of web-service specifications for links to many
other web-service standards, including those many whose names begin 'WS-'.
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Criticism
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Given the lack of set standards as to what "Web 2.0" actually means, implies, or requires, the
term can mean radically different things to different people.
Many of the ideas of Web 2.0 already featured on networked systems well before the term
"Web 2.0" emerged.
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Amazon.com, for instance, has allowed users to write reviews and consumer guides since its launch in
1995, in a form of self-publishing.
Amazon also opened its API to outside developers in 2002.
Prior art also comes from research in computer-supported collaborative learning and computersupported cooperative work and from established products like Lotus Notes and Lotus Domino.
Conversely, when a web-site proclaims itself "Web 2.0" for the use of some trivial feature
(such as blogs or gradient boxes) observers may generally consider it more an attempt at selfpromotion than an actual endorsement of the ideas behind Web 2.0.
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"Web 2.0" in such circumstances has sometimes sunk simply to the status of a marketing buzzword,
like "synergy", that can mean whatever a salesperson wants it to mean, with little connection to most
of the worthy but (currently) unrelated ideas originally brought together under the "Web 2.0" banner.
The argument also exists that "Web 2.0" does not represent a new version of World Wide Web at all,
but merely continues to use "Web 1.0" technologies and concepts.
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Criticism
• Other criticism has included the term "a second bubble", (referring to the
Dot-com bubble of circa 1995–2001), suggesting that too many Web 2.0
companies attempt to develop the same product with a lack of business
models. The Economist has written of "Bubble 2.0".[10]
• Venture capitalist Josh Kopelman noted that Web 2.0 excited only 53,651
people (the then number of subscribers to TechCrunch, a Weblog covering
Web 2.0 matters), too few users to make them an economically-viable
target for consumer applications.[11] (However, this criticism misses the
point that Web 2.0 applications may be embraced by millions of people such as the users of Wikipedia or MySpace - who benefit from the
networks without needing to understand the term 'Web 2.0' specifically).
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Criticism
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