Web 2.0
From Wikipedia, the free encyclopedia
The phrase Web 2.0 refers to a perceived second generation of web-based communities and hosted services — such as social-networking sites, wikis and folksonomies — which aim to facilitate collaboration and sharing between users. The term became popular following the first O'Reilly Media Web 2.0 conference in 2004,[1] and has since become widely adopted.
Although the term suggests a new version of the World Wide Web, it does not refer to an update to Web technical specifications, but to changes in the ways software developers and end-users use the web as a platform. According to Tim O'Reilly, "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."[2]
Some technology experts, notably Tim Berners-Lee, have questioned whether one can use the term in a meaningful way, since many of the technology components of "Web 2.0" have existed since the early days of the Web.[3]
[edit] Defining Web 2.0
Time bar of Web 2.0 buzz words.[4] This image shows the age of some buzzwords sometimes used in Web 2.0 lingo and its dependencies.
In alluding to the version-numbers that commonly designate software upgrades, the phrase "Web 2.0" may hint at an improved form of the World Wide Web. Advocates of the concept 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. Stephen Fry (actor, author and broadcaster) describes Web 2.0 as "an idea in people’s heads rather than a reality. It’s actually an idea that the reciprocity between the user and the provider is what’s emphasized. In other words, genuine interactivity if you like, simply because people can upload as well as download"[5].
As used by its supporters, 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"
- a pronounced distinction between functionality and web technology, enabling significantly easier development of new business-models and processes by using readily-available intuitive modular elements[6].
- enhanced organization and categorization of content, emphasizing deep linking
- a rise in the economic value of the Web, possibly surpassing[citation needed] the impact of the dot-com boom of the late 1990s
Earlier users of the phrase "Web 2.0" employed it as a synonym for "Semantic Web". The combination of social-networking systems such as FOAF and XFN with the development of tag-based folksonomies, delivered through blogs and wikis, sets up a basis for a semantic web environment.[citation needed]
Tim O'Reilly regards Web 2.0 as business embracing the web as a platform and utilising its strengths (global audiences, for example). O'Reilly considers that Eric Schmidt's abridged slogan, don't fight the Internet, encompasses the essence of Web 2.0 — building applications and services around the unique features of the Internet, as opposed to building applications and expecting the Internet to suit as a platform (effectively "fighting the Internet").
In the opening talk of the first Web 2.0 conference, Tim O'Reilly and John Battelle summarized what they saw as key principles of Web 2.0 applications:
- 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 so-called perpetual beta)
- software above the level of a single device, leveraging the power of the "Long Tail"
- ease of picking-up by early adopters
Tim O'Reilly provided examples of companies or products that embody these principles in his description of his four levels in the hierarchy of Web 2.0-ness:[8]
Level 3 applications, the most "Web 2.0"-oriented, which could only exist on the Internet, deriving their power from the human connections and network effects that Web 2.0 makes possible, and growing in effectiveness the more people use them. O'Reilly gave 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 (now part of Google Docs & Spreadsheets) and iTunes (because of its music-store portion).
Level 0 applications, which 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.
[edit] Characteristics of "Web 2.0"
While interested parties continue to debate the definition of a Web 2.0 application, a Web 2.0 website may exhibit some basic common characteristics. These might include:
- "Network as platform" — delivering (and allowing users to use) applications entirely through a browser.[9] See also Web operating system.
- Users owning the data on a site and exercising control over that data.[10][9]
- An architecture of participation that encourages users to add value to the application as they use it.[9][1] This stands in sharp contrast to hierarchical access-control in applications, in which systems categorize users into roles with varying degrees of functionality.
- A rich, interactive, user-friendly interface based on Ajax[9][1] or similar frameworks.
- Some social-networking aspects.[10][9]
The impossibility of excluding group-members who don’t contribute to the provision of goods from sharing 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.[11][12]
The concept of Web-as-participation-platform captures many of these characteristics. Bart Decrem, a founder and former CEO of Flock, calls Web 2.0 the "participatory Web"[13] and regards the Web-as-information-source as Web 1.0.
[edit] Technology overview
The complex and evolving technology infrastructure of Web 2.0 includes server-software, content-syndication, messaging-protocols, standards-based browsers with plugins and extensions, and various client-applications. These differing but complementary approaches provide Web 2.0 with information-storage, creation, and dissemination capabilities that go beyond what the public formerly expected of websites.
A Web 2.0 website may typically feature a number of the following techniques:
- rich Internet application techniques, optionally Ajax-based
- CSS
- semantically valid HTML 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 (partial use may grow to become the complete platform for the site)
- use of Open source software either completely or partially, such as the LAMP solution stack
- XACML over SOAP for access control between organisations and domains
- weblog publishing
- mashups
- REST or XML Webservice APIs
- use of user-friendly content-management systems (CMS). Such systems, often open-source based, can sometimes provide extensive website functionality at very low cost while reducing learning-curves.
- optimized search engine capability for frequently-used keywords
[edit] Innovations associated with "Web 2.0"
[edit] Web-based applications and desktops
The richer user-experience afforded by Ajax has prompted the development of websites 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. In 2006 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 operating-systems, 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.
[edit] Rich Internet applications
-
Recently, rich-Internet application techniques such as Ajax, Adobe Flash, Flex, Nexaweb, OpenLaszlo and Silverlight have evolved that can improve the user-experience 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.
[edit] Server-side software
Functionally, Web 2.0 applications build on the existing Web server architecture, but rely much more heavily 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 either under a universal server approach (which bundles most of the necessary functionality in a single server platform) or under a web-server plugin approach (which uses standard publishing tools enhanced with API interfaces and other tools).
[edit] 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, Silverlight or Java. These methods all make use of the client computer to reduce server workloads and to increase the responsiveness of the application.
[edit] XML and RSS
Advocates of Web 2.0 may regard syndication of site content as a Web 2.0 feature, involving as it does standardized protocols, which permit end-users to make use of a site's data in another context (such as another website, a browser plugin, or 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 XML-based formats. Observers have started to refer to these technologies as "Web feed" as the usability of Web 2.0 evolves and the more user-friendly Feeds icon supplants the RSS icon.
[edit] Specialized protocols
Specialized protocols such as FOAF and XFN (both for social networking) extend the functionality of sites or permit end-users to interact without centralized websites.
[edit] Web protocols
Web communication protocols support 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-'.
[edit] Web 2.0 and language-learning technologies
In second-language learning, some[citation needed] see Web 2.0 technologies as new and emerging technologies. Technologies such as on-demand video, file-sharing, blogs, wikis, and podcasting have become very popular with language-educators and students.[citation needed] Users of these technologies have emphasised their collaborative and community-building aspects, and suggested they form a natural ally for a constructivist learning methodology.[citation needed] A number of events sponsored by the International Association of Teachers of English as a Foreign Language (IATEFL) Learning Technologies SIG in the UK, Japan and India have focused on the use of Web 2.0 technologies to enhance language-learning environments.[citation needed]
[edit] Criticism
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 had already featured in implementations on networked systems well before the term "Web 2.0" emerged. 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.[14] Previous developments also came from research in computer-supported collaborative learning and computer-supported cooperative work and from established products like Lotus Notes and Lotus Domino.
Conversely, when someone proclaims a website "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 promotion than an actual endorsement of the ideas behind Web 2.0. "Web 2.0" in such circumstances has sometimes sunk simply to the status of a marketing buzzword, like "synergy", which 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. Note that techniques such as Ajax do not replace underlying protocols like HTTP, but add an additional layer of abstraction on top of them.
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."[15]
Venture capitalist Josh Kopelman noted that Web 2.0 excited only 53,651 people (the 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.[16]
[edit] Trademark
In November 2004, CMP Media applied to the USPTO for a service mark on the use of the term "WEB 2.0" for live events.[17] On the basis of this application, CMP Media sent a cease-and-desist demand to the Irish non-profit organization IT@Cork on May 24, 2006,[18] but retracted it two days later.[19] The "WEB 2.0" service mark registration passed final PTO Examining Attorney review on May 10, 2006, but as of June 12, 2006 the PTO had not published the mark for opposition. The European Union application (application number 004972212, which would confer unambiguous status in Ireland) remains currently pending after its filing on March 23, 2006.
[edit] See also
[edit] Various 2.0s
[edit] Related issues
[edit] References
[edit] External links
[edit] Supportive
[edit] Critical
