Web 2.0 - what is it?

Introduction
The term Web 2.0 (pronounced web two-point-oh) has been all over the Internet in the last few years. Almost every new application or innovative idea gets stamped as a Web 2.0 application. But what actually is Web 2.0? What does it stand for? What makes one application or company Web 2.0 and therefore hip and modern and others not?
The biggest problem with describing Web 2.0 is, that it means different things to different people. For one group it is the reinvention of the Web, while for others it is just a buzz word used to attract investors, and for yet another group it is just a transition state to new usage and interaction patterns of the Web - Web 3.0, to stay with the version numbering.
This report aims to give an explanation of the phenomenon Web 2.0 by first describing the origin of Web 2.0 and taking a look into definitions of what Web 2.0 is. Then key characteristics of Web 2.0 applications and companies are described. The facets of Web 2.0 are shown and underlined with examples of successful Web 2.0 applications. Finally, the question if Web 2.0 is a bubble is approached.

Origin
The term Web 2.0 was born 2003 in a brainstorming session between O'Reilly and MediaLive International. Core of this brainstorming session was a conference on web development, which should show that the Web was still important and produced continuously new and innovative sites and applications, although the Web lost popularity (especially with investors) after the 2001 dot-com crash. Dale Dougherty came up with the term Web 2.0 to describe some kind of turning point for the Web after the collapse and emphasize similarities between the companies of this new era.
Tim O'Reilly and John Battelle organized the first Web 2.0 Conference in October 2004. Co-producer was CMP Media, an event organization that bought MediaLive International. It became an annual conference and takes place for the third time in November 2006 in San Francisco. After the first conference Web 2.0 became a popular and widely used term to describe new Web developments of all kinds.
A controversy around the term Web 2.0' aroused in May 2006 when it became public that CMP Media filed for a service mark to protect the name Web 2.0 with respect to conferences and live events. Although the service mark was filed in 2003 before Web 2.0 became a synonym for everything new on the Web and it actually originated from O'Reilly it is argued that it is not directly associated with O'Reilly and therefore not a justified trademark (for more information about the controversity see Tom Raftery's blog entry about O'Reilly/CMP vs IT Cork, Tim O'Reilly's response and explanation and a BoingBoing article on the topic).

Characteristics
In the initial brainstorm session Web 2.0 was not formulated as a set of rules but as a list of examples which contrasted Web 1.0 and Web 2.0 approaches and applications: DoubleClick is Web 1.0, Google AdSense is Web 2.0. Personal websites (Web 1.0) versus blogs (Web 2.0). Akamai (Web 1.0) versus BitTorrent (Web 2.0). Britannica Online (Web 1.0) versus Wikipedia (Web 2.0). This list can be continued with numerous examples, but it only gives a feeling for Web 2.0, actually describing what makes one thing Web 2.0 and others not is harder.
Tim O'Reilly understood that problem and explained in his article What is Web 2.0? the initial understanding of Web 2.0. For O'Reilly Web 2.0 has no hard boundary and strong specifications. It is more a collection of loose principles that form the core of the concept Web 2.0. Websites, applications and services considered Web 2.0 use some (not necessary all) of those principles.
O'Reilly's compact definition of Web 2.0 summarizes those principles:

Web 2.0 is the network as platform, spanning all connected devices; Web 2.0 applications are those that make the most of the intrinsic advantages of that platform: delivering software as a continually-updated service that gets better the more people use it, consuming and remixing data from multiple sources, including individual users, while providing their own data and services in a form that allows remixing by others, creating network effects through an "architecture of participation," and going beyond the page metaphor of Web 1.0 to deliver rich user experiences.

An important part is to understand the Web as a platform rather than a way of presentation. Web applications are nowadays designed as services not as packaged software. Services are continuously improved by directly integrating user feedback. The traditional software release cycle is not applicable for Web 2.0 applications.
The main characteristics of Web 2.0 are users and data and how they are handled. Applications are based on an architecture of participation. In contrast to Web 1.0 data is now provided and created by users instead of companies. The user controls the data, applications only manage it and make it accessible to other users (including machines). Data from different sources can be combined to create new data and new applications. As a result systems and users are interconnected with each other. Data is better organized, easier accessible, and contains semantic structures. Companies can make use of the collective intelligence the data represents to improve their products and services.
Easy-to-use software interfaces open the interactive Web 2.0 world to a broader audience. Technical skills and knowledge are no longer necessary to activley participate in the Web community. Instead interactivity is promoted and individuals are encouraged to contribute and create data.
New technologies like XML, AJAX, RSS, or Ruby on Rails are also associated with Web 2.0 - they are the tools that make Web 2.0 work. Open source software and open standards are also an important part of Web 2.0. Most Web 2.0 services and applications are free. Companies do not make money by directly selling their products, they have to think of different business models. Integrating advertisements into products is one way, but there are better ways like offering professional support to enterprises and similar things.
Interesting is, that most Web 2.0 applications also show similarities in visual design (see build your very own Web 2.0 layout)and even in naming (see Quiz: Star Wars or Web 2.0?). Another thing that is typical for successful Web 2.0 businesses is that they all work without advertising themselves. Through the Web 2.0 community and especially through blogs new exciting services are promote mouth-to-mouth - viral marketing, another important part of Web 2.0.
Obviously, Web 2.0 can refer to a lot of different things. So it is not a surprise that most professionals have their own idea of Web 2.0 (see Stephen Briant's inoffical survey). Ian Davis wrote in an article that Web 2.0 is an attitude not a technology and that describes it quite well - it is not important to use a fancy technology like AJAX or yet another XML dialect, it is more important to attract new users and engage them to participate in actually shaping the service. Flickr, for example started off as a kind of online game and evolved into the leading photo sharing platform on the Web (see USA Today article on flickr's histroy).

Incarnations and Applications
As outlined above Web 2.0 can take many different shapes. In the following some typical Web 2.0 fields are described together with popular representants:

Blogging
Blogging is on of the most popular Web 2.0 activities. A blog (short for weblog) is the Web 2.0 version of a personal homepage combined with a personal diary. The core of a blog is a blog system, a web application that makes it easy for the user to create new entries without the need to know anything about HTML. Support for the integration of pictures and links are also provided.
A special feature of blogs is, that every entry has a unique and human-readable URL - a so called permalink. When a blogger uses a permalink to refer to a blog entry from a different blog, this blog is informed about the new link and a TrackBack is set. A TrackBack is nothing else than a reference to another resource where the blog entry was referenced. A kind of a two-way-link is established between the blogs.
Another feature of blogs is, that readers can comment on blog entries. In most blog systems commenting is possible without prior registration, which makes it easy for readers to express their thoughts but is also a vulnerability for spam.
Through TrackBacks and comments a social network between blogs with a high link density emerged, which is referred to as the blogosphere. The blogosphere is quite powerful, because of its strong interconnections. News can spread really fast in the blogging community.
People blog with different motivations, different topics and in different forms. Private and corporate blogs exist alike, topics range from day-to-day diaries over journalistic articles and news to special interests. Podcasting is another form of blogging where people record their entries as audio or video files. Podcasting was pushed by Apple through the iPod-iTunes combination.
Technorati is a popular search engine for blog entries.

Wikis
The most famous and first wiki is Wikipedia. A free encyclopedia where everybody can write new articles and edit any existing entry. That is the main concept behind wikis - information can be improved by everyone. The more people participate the better the quality of articles gets and the more extensive a wiki gets. As with Blogs editing of entries is done with a WYSIWYG editor or in the case of Wikipedia with structuring tags that are similar to HTML.
Wikis for all kind of topics emerged after Wikipedia, so did wiki software and providers like wetpaint, wikispaces or pbwiki where in some easy steps everybody can create an own wiki.

Social Tagging/Bookmarking
Tags are labels. Tags are quite popular in Web 2.0 and are applied to almost everything. A tag is a keyword that describes an entity, which can be a blog entry, a photo, a bookmark, a person or something else. The purpose of tags is to categorize information and make it more accessible. Tags can be freely chosen and are not predefined. Most social tagging systems support a rating system so that user can differentiate between valuable and uninteresting content.
del.icio.us and Furl are social bookmarking services that allow users to save, share and search bookmarks. Users can assign tags to links to enable better search results in the database.
Another site that relies on social tagging is digg. Digg is a user-driven news site where users can submit short news which refer to entries on other websites. The digg commnuity then diggs' interesting articles and the most popular articles are shown on digg's homepage.
Social tagging is also referred to as folksonomy because of it's user-driven nature and in contrast to a taxonomy where a small group of authors controls content and labels.

Social networking
Social networking describes online communities that allow users to communicate with each other and establish networks of friends. Normally a user has a profile and can add or invite friends to join. It is also possible to form groups and get to know new people through social connections or chats.
Some Social networking communities like myspace also allow users to share photos, sound or videos. Adding more features to the platform binds users closer to their community this way.
Some social networks restrict their service to regional areas to resemble social structures that exist in real life online. Facebook focuses on college communities for example. Business social networks exist as well. An example is openBC where members can establish business contacts in different industries. Like real social networks online business networks can help finding jobs or new projects.
Social networking has therefore multiple purposes. Friend networks aim to link friends to each other and share information or data (pictures, videos), while other networks actually aim for benefits, those can be knowledge through communication or even financial benefit in the case of business networks.

Media and Entertainment
Web 2.0 is all about sharing information and data. Numerous systems assist users in making data easily available on the Web. Youtube is a good example. Youtube allows user to upload videos which are then made accessible by converting them into Flash-Videos. This is the key to youtube's success. In contrast to other media formats like Quicktime or Windows Media, which often have compatibility or playback problems, Flash can be viewed by a majority of Internet users due to the broad distribution of the Flash-Plugin. As a result youtube is now one of the leading resources for videos online.
A popular picture management service is flickr. Flickr users can share pictures with friends or with the public and tagging is used to improve the accessibility and search for pictures. Flickr is also a kind of social network and also incorporates blog support, which enables users to directly blog pictures found on flickr.
Pandora is an individually customized radio station. A new user enters the title of a song or a band and then pandora suggests and plays music from it's database that shows similar patterns to the specified song. The user can then specify if the suggested song is liked or disliked and thereby improve the quality of suggestions. The aim behind pandora is to introduce people to music they don't know but might like. The interface also contains links to buy played songs at online music stores.

Online Applications
Some Web 2.0 applications take traditional desktop applications and transport them to the Web. Those applications utilize AJAX to provide the online application with the same look-and-feel and even more important the same degree of interactivity as a desktop application.
Office applications like word processors are quite suitable for the Web. Using an online word processor has advantages over desktop based systems: software and files are accessible from every computer with an Internet connection and can even be shared with colleges and friends - rendering sending of files as email attachments obsolete. Writley is such an online word processor, it has been acquired by Google recently and will maybe part of a Google office suite with Google Spreadsheets, an online spreadsheet application which is not yet lunched but can be previewed here. Another online office suite is provided by Zoho, it includes presentation, word processor, spreadsheet and calendar applications.
Meebo is an online instant messaging client. It supports AIM/ICQ, MSN, Yahoo! Messenger and Jabber/GTalk. The user can login with several protocols simultaneously. Meebo resembles a traditional desktop IM client: contacts are organized in a contact list and messages are shown in windows, which are part of the interface.

There is more
Obviously, the list of Web 2.0 applications and purposes is endless. It is hard or alost impossible to put Web 2.0 applications into categories like done above. Most of the listed applications would also fit in other categories or even show features of all categories. There are also applications that do not fit in the given categories at all. Google Maps for example. Google Maps presents maps in combination with satellite images in an interactive AJAX interface. Users can use the Google Maps API to integrate Google Maps into their own applications - clearly Web 2.0, but which category to put it into?
The latest trend in the Web 2.0 community are mash ups. Mash ups are combinations of two or more applications to create something new. Placeopedia combines Wikipedia and Google Maps - locations are linked to associated Wikipedia articles. Liveplasma shows search results for artists or movies as semantic webs and visualizes connections between entities. Other applications like Ning even support users in creating their own mash ups.
The possibilities of applications and combinations are endless. Seomoz.org, a search engine optimization company, honors the most innovative and successful Web 2.0 sites every year with the Web 2.0 Awards. Their list of winners and nominees contains almost 300 Web 2.0 applications and sites, it gives a good overview of Web 2.0 applications and their capabilities.

Is it a Bubble?
Web 2.0 is big at the moment, and it is also a nice marketing buzz word to attract investors. Everyday new applications and companies come into existence that label themselves Web 2.0, without understanding what Web 2.0 is about. Of course, there are also lots of new, interesting and useful applications out there and they are praised and appreciated in even more blogs and podcasts but at the end of the day only Internet enthusiasts know about them and even fewer actually use them. The broad population has no idea about the possibilities of Web 2.0.
That is one reason why critics predict that Web 2.0 will end in a crash similar to the end of the dot-com boom. But is that really bad? After all, the Web industry recovered very well after the crash and is flourishing again. In a new crash small companies and companies without understanding for Web 2.0 will vanish. Promising applications might be bought by one of the bigger companies. But companies that are flexible enough to adapt to changes can survive a crash. Good examples are Google or Yahoo!, both companies existed before the dot-com crash and are now on top of the Web 2.0 movement. Both continuously acquire smaller Web 2.0 start-ups and incorporate them into their services. Yahoo! gulped flickr and del.icio.us at the end of last year and its product range covers now almost all parts of the Web 2.0 world after the recent addition of Yahoo! 360 as a social network to its portfolio.
Google also offers a broad range of services. And most of Google's releases became instant successes because of their innovative nature. Gmail was the first email provider without storage limitations, Google Maps and Google Earth are based on a commercial software from keyhole Inc. that Google acquired in 2004, the Google Maps API is now used in many Web 2.0 mash-ups. Google video provides sharing of videos similar to youtube. Blogger provides free blogs, orkut is Google's social network and the list of Google services is even longer.
So maybe Web 2.0 is a hype, but it is a quite profitable hype at the moment. It might even gain more attention when applications and services are discovered and used by a broader audience. The time might come, when a new shake-down will separate those businesses that fully understand and utilize the Web 2.0 from those that do not get Web 2.0 and just use it as a buzz word. Companies that are able to bind users to their services will last. And no one can predict what future developments will change the Web - no one thought of Ajax before Jesse James Garrett published his ideas, although Ajax is just a combination of already well known technologies. With tagging, editable web sites (wikis) and trackbacks/permalinks as simple two-way links Web 2.0 comes closer to Tim Berners Lee's vision of the Internet but it is not there yet. Evolution into a semantic web as Tim Berners Lee promotes it might be the next step for the Web, but maybe the Web takes a different direction. It is almost impossible to predict the future of the Web. Only time can tell what technologies will last or which trends the Web will follow, in the meanwhile we can enjoy the new degree of interactivity that Web 2.0 brought to the Web.

Resources and interesting links
- Wikipedia article about Web 2.0 (retrieved 09.08.2006).
- Tim O'Reilly - What is Web 2.0 from 2005 (retrieved 09.08.2006).
- O'Reilly's Guide to Web 2.0, Interview with Tim O'Reilly, Businessweek online podcast, 06.05.2006 (retrieved 09.08.2006).
- Dion Hinchcliffe - The State of Web 2.0, 02.04.2006 (retrieved 10.08.2006).
- Dion Hinchcliffe - Thinking in Web 2.0: Sixteen Ways, 25.02.2006 (retrieved 11.08.2006).
- Ian Davis - Talis, Web 2.0 and all that, 04.05.2005 (retrieved 09.08.2006).
- Newsweek article: The new Wisdom of the Web, 03.04.2006 (retrieved 09.08.2006).
- Technology Review article: Web 2.0 has arrived>/a>, 07.10.2005 (retrieved 09.08.2006).
- USA Today article: flickr of idea on a gaming project led to photo website, 28.02.2006 (retrieved 08.08.2006).
- The Web 2.0 Awards Zeitgeist (retrieved 09.08.2006).
- Tim O'Reilly - Not 2.0?, 05.08.2005 (retrieved 09.08.2006).
- Slate article: Web 2.0 doesn't live up to its name", 29.03.2006 (retrieved 09.08.2006).
- Jeffrey Zeldman - Web 3.0, 16.01.2006 (retrieved 08.08.2006).
- Jesse - James Garret - AJAX: A new approach to web applications, 18.02.2005 (retrieved 08.08.2006).
- Tim Berners Lee - The Future of the Web. audio and video recordings of a speech from 14.03.2006 (mp3 retrieved 13.08.2006).
- Tim Berners Lee - The original proposal of the World Wide Web, 1989, HTML version (retrieved 08.08.2006).
- The Web 2.0 Conference (O'Reilly Media/CMP Media).
- The SEOmoz.org Web 2.0 awards.
- The Web 2 Journal.
- The Web 2.0 workgroup.