What is Web 2.0? Nowadays, almost everything is “tagged” as Web 2.0. Companies, sites, ideas, etc. So, as teh old saying goes, if everything was Web 2.0,  then nothing would be Web 2.0.

Web 2.0 refers to a generation of internet applications. The ones shifting the importance from the server and the “deux ex-machina” content creator, to the end-users and their clients. Wiki tells us the phrase “Web 2.0″ hints at an improved form of the World Wide Web. Technologies such as weblogs, social bookmarking, wikis, podcasts, RSS feeds (and other forms of many-to-many publishing), social software, web application programming interfaces (APIs), and online web services such as eBay and Gmail provide a significant enhancement over read-only websites. 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”. The phrase “Web 2.0″ can also refer to the transition of websites from isolated information silos to interlinked computing platforms that act like software to the user. Web 2.0 also includes a social element where users generate and distribute content, often with freedom to share and re-use. The result is a rise in the economic value of the Web as users can do more online.

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.

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”).
On September 30, 2005, Tim O’Reilly wrote a piece summarizing the subject. The mind-map pictured above (constructed by Markus Angermeier on November 11, 2005) sums up the memes of Web 2.0, with example-sites and services attached.
On September 30, 2005, Tim O’Reilly wrote a piece summarizing the subject. The mind-map pictured above (constructed by Markus Angermeier on November 11, 2005) sums up the memes of Web 2.0, with example-sites and services attached.

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. 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.

These are some leading European Social Networks, as described by their own creators:

Grono.net: “grono.net is a site, which gathers people belonging to a closed community, in which you may find your friends and collegues - and they may find you! Our system registers your contacts and shows who - through your existing contacts - may become your friend, and which is the shorthest path between you in the chain of friends. At the same time, you have as much privacy as you want - you decide which data or personal information you want to show the others. To register in our community you have to have an invitation from someone who is already our member.”

Neogen.ro: “portal de joburi, matrimoniale, cluburi, network, stiri, anunturi, publicitate, catalog, jocuri multiplayer, hosting, monitor, albume foto, content mobil si multe alte produse si servicii online pentru consumatori si firme.” More or less: portal for work, weddings, clubs, sites, classifieds, etc.

NetLog: “Netlog is an online social portal specifically targeted at the European youth. It is developed by Netlog NV, the Belgium-based publisher of popular online social media. Netlog has more than 26.2 million members throughout Europe. Netlog is currently available in eight languages – English, French, Spanish, German, Portuguese, Dutch, Italian and Romanian – with all other European languages to be added in the near future. n Netlog, members can create their own web page, extend their social network, publish their music playlists, share photos and videos, post blogs, join groups called ‘clans’ and much more. It is thus the ultimate tool for young Europeans to connect and communicate with their social network.”

Read the full story on the Web 2.0 in Europe blog. Get in touch with other Web 2.0 users on the European social network: social media in Europe.

Topics:Web 2.0, Neogen.ro, Grono.net, IWIW.HU, Rate.ee, MySpace.com, Orkut.com

RSS stands for “Really Simple Syndication”, while Atom is an XML language used for web feeds. Confused or want to know more? You can read the Web 2.0 blog for further information about RSS, Atom and Web 2.o in general; or Network with other Web 2.0 users on the social network for development and Peace; or simply read the overview we publish below. Wiki docet

BLOG RSS: Rss 

RSS is a family of Web feed formats used to publish frequently updated content such as blog entries, news headlines or podcasts. An RSS document, which is called a “feed”, “web feed”, or “channel”, contains either a summary of content from an associated web site or the full text. RSS makes it possible for people to keep up with their favorite web sites in an automated manner that’s easier than checking them manually. RSS content can be read using software called a “feed reader” or an “aggregator.” The user subscribes to a feed by entering the feed’s link into the reader or by clicking an RSS icon in a browser that initiates the subscription process. The reader checks the user’s subscribed feeds regularly for new content, downloading any updates that it finds.

The initials “RSS” are used to refer to the following formats:

- Really Simple Syndication (RSS 2.0)
- RDF Site Summary (RSS 1.0 and RSS 0.90)
- Rich Site Summary (RSS 0.91)

RSS formats are specified using XML, a generic specification for the creation of data formats.

ATOM USAGE

Web feeds are used by the weblog community to share the latest entries’ headlines or their full text, and even attached multimedia files. (See podcasting, vodcasting, broadcasting, screencasting, Vloging, and MP3 blogs.) These providers allow other websites to incorporate the weblog’s “syndicated” headline or headline-and-short-summary feeds under various usage agreements. Atom and other web syndication formats are now used for many purposes, including journalism, marketing, bug-reports, or any other activity involving periodic updates or publications. Atom also provides a standardized way to export an entire blog, or parts of it, for backup or for importing into other blogging systems. A program known as a feed reader or aggregator can check webpages on behalf of a user and display any updated articles that it finds. It is common to find web feeds on major Web sites, as well as many smaller ones. Some websites let people choose between RSS or Atom formatted web feeds; others offer only RSS or only Atom. In particular, many blog and wiki sites offer their web feeds in the Atom format.

Client-side readers and aggregators may be designed as standalone programs or as extensions to existing programs like web browsers. Browsers are moving toward integrated feed reader functions, such as Safari RSS, Web Browser for S60, Opera, Firefox and Internet Explorer. Such programs are available for various operating systems. Web-based feed readers and news aggregators require no software installation and make the user’s “feeds” available on any computer with Web access. Some aggregators syndicate (combine) web feeds into new feeds, e.g., taking all football related items from several sports feeds and providing a new football feed. There are also search engines for content published via web feeds, including Technorati and Blogdigger.

Atom Compared to RSS 2.0 

One difference between the two is that RSS 2.0 may contain either plain text or escaped HTML as a payload, with no way to indicate which of the two is provided, while Atom uses an explicitly labeled (i.e. typed) “entry” (payload) container. It allows for a wider variety of payload types including plain text, escaped HTML, XHTML, XML, Base64-encoded binary, and references to external content such as documents, video and audio streams, and so forth. Other differences include:
- RSS 2.0 has a “description” element which can contain either a full entry or just a description. Atom has separate “summary” and “content” elements. Atom thus allows the inclusion of non-textual content that can be described by the summary.
- Atom is defined within an XML namespace whereas RSS 2.0 is not.
- Atom specifies use of the XML’s built-in xml:base for relative URIs. RSS 2.0 does not have a means of differentiating between relative and non-relative URIs.
- Atom uses XML’s built-in xml:lang attribute as opposed to RSS 2.0’s use of its own “language” element.
- In Atom, it is mandatory that each entry have a globally unique ID, which is important for reliable updating of entries.
- Atom 1.0 allows standalone Atom Entry documents whereas with RSS 2.0 only full feed documents are supported.
- Atom specifies that dates be in the format described in RFC 3339 (which is a subset of ISO 8601). The date format in RSS 2.0 was underspecified and has led to many different formats being used.
- Atom 1.0 has IANA-registered MIME-type. RSS 2.0 feeds are often sent as application/rss+xml, although it is not a registered MIME-type.
- Atom 1.0 includes an XML schema. RSS 2.0 does not.
- Atom is an open and evolvable standard developed through the IETF standardization process. RSS 2.0 is not standardized by any standards body. Furthermore according to its copyright it may not be modified.
- Atom 1.0 elements can be used as extensions to other XML vocabularies, including RSS 2.0 as illustrated in a weblog post by Tim Bray entitled “Atomic RSS”.
- Atom 1.0 describes how feeds and entries may be digitally signed using the XML Digital Signature specification such that entries can be copied across multiple Feed Documents without breaking the signature.
- Despite the emergence of Atom as an IETF Proposed Standard and the decision by major companies such as Google to embrace Atom, use of the older and more widely known RSS 1.0 and RSS 2.0 formats has continued.
- RSS 2.0 support for enclosures led directly to the development of podcasting. While many podcasting applications, such as iTunes, support the use of Atom 1.0, RSS 2.0 remains the preferred format [5].
- Many sites choose to publish their feeds in only a single format. For example CNN, the New York Times, and the BBC offer their web feeds only in RSS 2.0 format.
- News articles about web syndication feeds have increasingly used the term “RSS” to refer generically to any of the several variants of the RSS format such as RSS 2.0 and RSS 1.0 as well as the Atom format. (For example, “Fine-Tuning Your Filter for Online Information” (NYT) and “There’s a Popular New Code for Deals: RSS” (NYT January 29, 2006))
- Each of the various web syndication feed formats has attracted large groups of supporters who remain satisfied by the specification and capabilities of their respective formats.
- Atom supports multiple link elements per entry, a feature which can be used to specify enclosures of different types. This eliminates the need for separate feeds for podcasts that provide multiple file formats.

Web 2.0 Deutschland - Danke schoen Open Directory Web 2.0 in Europe blog und Europeische social network - Europeische Web 2.0.

Web 2.0 Deuschland:

• Chance Web 2.0 - Der Fachkongress fand im September 2006 in Köln statt und bot eine Plattform zum Wissens- und Meinungsaustausch zu den Chancen und Risiken des Web2.0. Mit Referentenliste, Blog und einer Bildergalerie.
• Innovationsprogramm Web 2.0 - Programm aus Baden-Württemberg, was die wirtschaftlichen, technischen und sozialen Chancen und Risiken ausloten soll. Die Arbeitskreise betrachten insbesondere Aspekte des Wissensmanagements, Marketings sowie PR und analysieren und bewerten Geschäftsmodelle. Ein Web2.0-Wettbewerb sowie eine Veranstaltungsreihe begleiten das Projekt.
• Social Software und so - Olaf Nitz schreibt in seinem Weblog über den Einsatz von Social Software in der Unternehmenskommunikation. Insbesondere geht es um Blogs, Wikis sowie Aspekte des User Generated Contents.
• Social Web World - Kongress Media GmbH - Das Unternehmen veranstaltet Workshops, Fachkongresse und andere Events, auf denen Aspekte des Mitmach-Webs aus Unternehmensperspektive diskutiert und vertieft werden.
• Socialweb Guide - In dem Portal werden Web2.0 Anwendungen gesammelt und bewertet.
• Der Web 2.0 Report - Die Analyse des Phänomens Web 2.0 aus User-, Technik- und Businessperspektive richtet sich an Entscheider sowie Strategen und kann kostenpflichtig bestellt werden.
• Web 2.0 Sammelalbum - Enthält eine Zusammenfassung von Web 2.0 Anwendungen, wozu neben Bookmarksammlungen und News-Communities auch Video-Plattformen gehören. Die vorgestellten Anwendungen können zudem bewertet und kommentiert werden.
• Web 2.0: Web Competence und Web Responsibility - In einer virtuellen Runde wurden Medienfachleute und Web2.0-Unternehmer nach den Chancen und Risiken sowie der Bedeutung des Mitmach-Webs befragt.
• Web Business 2.0 - Web Business 2.0 ist ein Weblog von active value über Internet-Technologie, Business Kommunikation und Web 2.0-Themen.
• Zweinull.cc - Betrachtet die nationale und internationale Entwicklung des Web 2.0 aus Marketing- und Entwicklerperspektive.

RSS info:

• Alesti RSS Leser - Freier Web 2.0 RSS-Feed-Leser. Es werden alle vorhandenen Feed-Formate wie RSS und Atom unterstützt.
• Alnera RSS Software - Anbieter von RSS Software zum Lesen und Erstellen von Newsfeeds.
• Bloggerei.de - Viele interessante Blog Beiträge via RSS Feed im Blogverzeichnis.
• Dr.Web Weblog - Dr.Web befasst sich mit den unterschiedlichsten Themen im RSS Bereich.
• Feedbar - Informationen zum Sharewareprodukt Feedbar, einer Toolbar mit einer interaktiven Laufschrift.
• FeedCMS - Frei verfügbares Content-Management-System zur Erstellung und Verwaltung von Newsfeeds.
• Feed2mail.org - Script für eine Mailingliste mit dem Inhalt eines RSS-Feeds.
• Feed-Maker - Erstellt ein konfigurierbares JavaScript von einem RSS-Feed.
• Feed-Reader.net - Ermöglicht RSS-Feeds online zu lesen. Bietet darüberhinaus ein kleines Verzeichnis von RSS-Feeds sowie eine Liste mit häufig gestellten Fragen.
• Häufig gestellte Fragen zum Thema RSS - Beantwortet grundlegende Fragen, demonstriert das Format anhand einer Beispieldatei und erläutert die Entstehungsgeschichte.
• Hungry For Feeds - Einfacher und werbefinanzierter RSS-Reader für Windows.
• It-reader.de - Frei verfügbarer RSS Newsreader zum Download.
• IzyNews - Bietet einen Dienst an, um Nachrichten in einer Mail zu empfangen. Schwerpunkte sind Nachrichten, Aktuelles sowie Immobilien- und Stellenangebote.
• Kleines Format ganz groß - Bietet eine Übersicht über die Entwicklungsgeschichte und erläutert anhand von Beispielen das Datenformat und die verschiedenen Anwendungsmöglichkeiten.
• NewsBee - Vorstellung der Produktversionen vom RSS-Reader NewsBee für Windows. Downloadmöglichkeit vorhanden.
• NewsNow - Online Newsreader für RSS Feeds.
• news.seekxl.de - Kategorisierte Online News im RSS Format.
• RSS Blogger - Das Blog von Siegfried Hirsch beschäftigt sich mit Nutzen und Anwendung der Content Syndication mit Hilfe von WebFeeds und den Formaten RSS, RDF und Atom.
• RSS kurzgefasst - Gibt eine Übersicht zu Entstehung und Nutzung des Datenformats und erläutert den Aufbau von RSS-Dateien anhand von Beispielen.
• RSScrawler - Shareware-Programm, welches beliebige RSS-Feeds im Stil eines Newstickers auf dem Windows-Desktop anzeigt.
• RSS-Forum - Diskussionen und Informationen zu neuen Feeds, zur Entwicklung von RSS sowie zu Software.
• RSS-guck - Downloadseite des freien Readers RSS-guck.
• RSS-Monitor - RSS-Feeds online lesen und verwalten.
• rssNEWS.de - Erstellt einen Newsticker mit den selbst angegebenen RSS-Feeds für die eigene Homepage.
• RSS-Newsfeed - Bietet eine kurze Einführung zum Thema sowie zahlreiche Links zu Seiten mit derartigen Feeds sowie zu Anbietern von Readern.
• Rss2pdf.org - Service zur Erstellung von PDF Dokumenten aus RSS Feeds, um diese ohne RSS-Reader zu lesen.
• RSS-Readers - Weblog zu RSS Feeds und Aggregatoren.
• RSS-Scout.de - Auflistung von Anbietern zu RSS Reader, Tools, Quellen und die größte deutsche Auswahl an RSS Feeds.
• Schockwellenreiter: Was ist RSS? - Bietet einen Überblick über das Dateiformat und gibt Hinweise für Entwickler.
• Scouty - Ein online Feedreader und 24h Nachrichtenportal, welches tagesaktuelle Nachrichten sammelt und auf einen Blick darstellt.
• Surfen ist out - Diskutiert die Möglichkeiten und Perspektiven der Nutzung und führt das benötigte Rüstzeug auf.
• XML-Feed.de - Plattform für Content-Services sowie Tipps, Tricks und eine Community.

Ajax:

• AJAX Community - Forum für Asynchronous JavaScripting and XML.
• AJAX in Action - Die Fachkonferenz widmet sich in Workshops und Vorträgen dem Thema AJAX auf Client- und Server-Seite. Begleitet wird das Forum von einer kleinen Hausmesse. Mit Programminfos, Profilen von den Referenten sowie einer Bildergalerie.
• Ajax Info - Das Weblog stellt aktuelle AJAX-Anwendungen vor und enthält diverse Tutorials.
• AjaxTalk.de - Forum-Community zum Thema AJAX - „Asynchronous JavaScripting and XML“.
• Praxiswissen AJAX - Die Website zum gleichnamigen Buch von Denny Carl mit einem Probekapitel, aktuellen Meldungen sowie Quelltexte zum Download.

Web 2.0 en Francais - Merci Open Directory Web 2.0 in Europe blog. et European social network.

Topics:<strong>Web 2.0, </strong>

• AccessOWeb le Blog - Interview, tests, billets rédigés à plusieurs mains autour de l’utilisation des services 2.0.
• Alterclickr - Marc Thouvenir présente son appproche personnelle du web 2.0 et de l’évolution de l’internet.
• Esclavage 2.0 : Eux, nous et moi - Karl Dubost compare le web 2.0 à une nouvelle forme d’esclavage, analyse critique de l’utilisation des données personnelles sur certains sites.
• Glossaire des termes 2.0 - Ajax, Mash-up, Wiki et bien d’autres. De nouveaux mots apparaissent avec le web 2.0, en voici les principales définitions enrichies d’exemples.
• Le groupe de travail Web2.0 francophone - Réseau de blogues francophones attentifs à la renaissance du web. Les membres du groupes ont pour but de diffuser les nouveautés, bonnes pratiques et initiatives innovantes, collaboratives, ouvertes qui soutendent ce phénomène connu sous le nom de web2.0.
• 2803, le blog - Blog qui traite avant tout de l’évolution de l’internet avec en particulier le phénomène du web 2.0, avec des informations sur les nouveaux services ainsi qu’une approche business de ces services 2.0.
• Techcrunch - Traduction en français du célèbre blog américain sur l’actualité du Web 2.0. Le traducteur y ajoute également quelques news spécifiquement françaises.
• La Voix du Savoir - L’objectif de la Voix du Savoir est de vocaliser les articles de l’encyclopédie Wikipedia en format podcast.
• Le web 2.0, c’est pas du buzz - Blog qui tend à prouver cette affirmation.
• Le Web 2.0 en mouvement - Ce blog fournit des explications en français et regroupe les dernières applications de ce concept. De digg, au blog, en passant par del.icio.us ou encore meebo. Cette technologie offre un web, construit tel une communauté d’utilisateurs, en interaction.
• Web 2.0 francophone - Présentation du web 2.0 francophone, à travers les sociétés, les blogs, wikis et sites qui le composent et qui en parlent.
• Web 2 You - Actualité du web 2.0, description et critique des nouveaux sites et services, tutoriaux sur les fonctionnalités du web 2.0.
• Webdeux - Jean-François Ruiz découvre, teste et décortique les usages des nouveaux outils 2.0
• Wiki francophone du web .2.0 - Le but de ce wiki est de suivre l’évolution du web 2.0 par la communauté francophone via un répertoire des services.
• Wikipédia : Web 2.0 - Présentation, origine du terme, explications sur les technologies et liens.
• AgoraVox : Fragilité économique de Web 2.0 - Un article de Francis Pisani résume les principales prises de positions lors de la récente conférence de l’Expo Web 2.0 à San Francisco. (May 7, 2007)
• Web 2.0 : risques et perspectives - Eric van der Vlist fait le point sur les évolutions du Web 2.0, ses risques et ses perspectives et précise la définition du terme. (December, 2006)
• Mashups, applications Web composites très Web 2.0 - Cet article du JDN Solutions présente les mashups, mutualisation des contenus en s’appuyant sur des services déjà existants. (June 28, 2006)
• Temesis : La vraie rupture 2.0 - Un article d’Elie Sloïm pour qui le passage au Web 2.0 a été rendu possible par l’apparition des CMS (systèmes de gestion de contenus). (June 9, 2006)
• Folksonomies, les usagers indexent le web - Olivier Le Deuff, dans cet article du Bulletin des bibliothèques de France (BBF) fait le point sur le principe et les usages des folksonomies (indexation sociale) et de leur système de “tag” : définition, historique et débats en cours. (2006)
• Web 2.0 : la révolution par les usages - Un article de Frédéric Cavazza destiné au grand public explique ce qu’est le Web 2.0. (December 19, 2005)
• Web 2.0 : mythes et réalités - Le Web 2.0 représente une avancée dans l’utilisation des technologies sur le Web.

Ajax - Francais

• Ajax - Club d’entraide des développeurs francophones - Rubrique Ajax du club d’entraide des développeurs francophones : tutoriels, cours, FAQ, livres et forum Ajax.
• Ajax : premiers pas - Article présentant Ajax et proposant deux exemples concrets pour débuter.
• Ajax - une autocomplétion pas à pas - Découverte de ce qu’est AJAX à travers un tutoriel permettant de créer une interface d’aide à la saisie.
• Ajax et XMLHttpRequest - Présentation et spécifications d’Ajax, avec tutoriel permettant d’acquérir de premières notions sur cette méthode de développement.
• Mozilla - documentation Ajax - Documentation Ajax pour débutants à confirmés.
• L’objet XMLHttpRequest - Traduction en français de la spécification W3C, la base d’Ajax.
• XMLHTTPRequest - Tutoriel sur l’utilisation des requêtes serveur en javascript.
• Ajax : une nouvelle approche pour les applications web - Cette traduction française de l’article de Jesse James Garrett, à l’origine du terme Ajax, présente cette approche du web et la compare à l’approche traditionelle. (February 18, 2005)

Topics: web 2.0, ajax web 2.0, application web 2.0, applications web 2.0, best web 2.0, blog web 2.0, cms web 2.0, definition web 2.0, le web 2.0, logo web 2.0, logos web 2.0, marketing web 2.0, microsoft web 2.0, mobile web 2.0, net web 2.0, o reilly web 2.0, services web 2.0, sites web 2.0, technologies web 2.0, the web 2.0, tutorial web 2.0, web 2.0 blogs, web 2.0 business, web 2.0 conference, web 2.0 design, web 2.0 framework

A Mashup is an applications combining and merging information in ways which may, or may be not, be the ones intendend by the site(s) where the information where collected in the first place. With mashups, the focus shifts from the application to the information which populate it. To make it brief: information rule

Hip-hop lent this term to Web 2.0, because originally mashup meant to produce a new song by mixing two or more existing pieces. As Wiki says, mashups currently come in three general flavors: consumer mashups, data mashups, and business mashups.

The most well-known type is the consumer mashup, best exemplified by the many Google Maps applications. Consumer mashups combine data elements from multiple sources, hiding this behind a simple unified graphical interface.

Other common types are “data mashups” and “enterprise mashups“. A data mashup mixes data of similar types from different sources, as for example combining the data from multiple RSS feeds into a single feed with a graphical front end. An enterprise mashup usually integrates data from internal and external sources - for example, it could create a market share report by combining an external list of all houses sold in the last week with internal data about which houses one agency sold.

A business mashup is a combination of all the above, focusing on both data aggregation and presentation, and additionally adding collaborative functionality, making the end result suitable for use as a business application.

Mashups and Portals are both content aggregation technologies. Portals are an older technology designed as an extension to traditional dynamic web applications, in which the process of converting data content into marked-up web pages is split into two phases - generation of markup “fragments” and aggregation of the fragments into pages. Each of these markup fragments is generated by a “portlet”, and the portal combines them into a single web page. Portlets may be hosted locally on the portal server or remotely on another server.

Portal technology defines a complete event model covering reads and updates. A request for an aggregate page on a portal is translated into individual read operations on all the portlets that form the page (”render” operations on local, JSR 168 portlets or “getMarkup” operations on remote, WSRP portlets). If a submit button is pressed on any portlet on a portal page, that is translated into a single update operation on that portlet alone (”processAction” on a local, JSR 168 portlet or “performBlockingInteraction” on a remote, WSRP portlet). The update is then immediately followed by a read on all portlets on the page.

Portal technology is about server-side, presentation-tier aggregation. It cannot be used to drive more robust forms of application integration such as two-phase commits.

Read the full story on the Web 2.0 in Europe blog. Get in touch with other Web 2.0 users on the European social network: social media in Europe.

Topics: mashup, ajax mashup, map mashup, mashup download, mashup mp3, mashup music, mashup software, Web 2.0