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3.9  Tagging

History of Tagging

Tagging, or labeling content, is part of the collaborative nature of Web 2.0. A tag is any user-generated word or phrase that helps organize web content and label it in a more human way. Though standard sets of labels allow users to mark content in a general way, tagging items with self-chosen labels creates a stronger identification of the content. In an interview by the Pew Internet & American Life Project, David Weinberger (author of Everything is Miscellaneous) said:

Maybe the most interesting thing about tagging is that we now have millions and millions of people who are saying, in public, what they think pages and images are about.

—David Weinberger

As part of the same December 2006 report, 28% of Internet users had reportedly “tagged” content online.1

Tag Clouds

Tag Clouds are visual displays of tags weighted by popularity. Many Web 2.0 sites include a graphical representation of popular tags (the popularity of the tag marked by the size of its text). There are many ways of forming tag clouds—terms often appear in alphabetical order. However, tag clouds show only how the majority (or the crowd) thinks and disregard many individual unique points of view.2 Figure 3.3 is an example of a “text cloud” that we created manually from the major terms in this chapter. (To build your own text cloud try ArtViper’s TextTagCloud tool at


Fig. 3.3 | Text cloud of major Web 2.0 terms from this chapter.

text cloud of Web 2.0 companies, concepts, technologies, etc.


Folksonomies are classifications based on tags. The term is generally attributed to Thomas Vander Wal, who combined the words “taxonomy” and “folk” to create a new term for this Internet phenomenon.3 Folksonomies are formed on sites such as Flickr, Technorati and Users can search content by tags, which identify content in different (and sometimes more meaningful) ways than traditional keywords used by search engines.

An example of Web 2.0’s reach outside of traditional technology fields can be seen in the project, an experiment in tagging and folksonomies regarding museum collections. In 2005, The Metropolitan Museum of Art and the Guggenheim Museum organized a retreat to plan the project.4 In 2007 they posted various collections of art online and asked the community for help tagging them.


Flickr—a popular photo-sharing site—was launched in February 2004 and acquired by Yahoo! in 2005. The Flickr development team was originally working on “The Game Neverending”—a multiplayer Flash game based on IM (instant message) and chat interfaces.5 However, the team listened to its users and developed real-time photo sharing (Flickr Live) and more traditional web pages where users could view uploaded pictures. The Game Neverending and Flickr Live were later retired as the popularity of photo sharing and commenting on the web pages grew.6

Flickr is a key content-tagging site. Intended as a way of organizing personal photo collections, tagging on the site gained popularity as the community became interested in “a global view of the tagscape” (how other people are tagging photos).7 Users can search for photos by meaningful tags. The tags also encourage loyalty to the site, since the tags are lost if photos are moved to another site.


Technorati, a social media search engine, uses tags to find relevant blogs and other forms of social media. To become searchable by Technorati, bloggers can add tags to their posts with a simple line of HTML or use the automated category system offered by some blogging software packages.8 Technorati tag searches return results from the blogosphere, YouTube videos and Flickr photos. Technorati features a tag cloud on its homepage and a “where’s the fire” section to promote the most popular tags and search results.



  1. Rainie, L. “Tagging.” Pew Internet & American Life Project, 31 January 2007. <http://www.pewin>.
  2. Rainie, L. “Tagging.” Pew Internet & American Life Project, 31 January 2007. <http://www.pewin>.
  3. Vander Wal, T. “Folksonomy Coinage and Definition.”, 2 February 2007 <>.
  4. Chun, S., R. Cherry, D. Hiwiller, J. Trant and B. Wyman. “ An Ongoing Experiment in Social Tagging, Folksonomy, and Museums.” Archives & Museum Informatics, 1 March 2006 <>.
  5. Schonfeld, E. “The Flickrization of Yahoo!” CNN, 1 December 2005 <>.
  6. Garrett, J.J. “An Interview with Flickr’s Eric Costello.” Adaptive Path, 4 August 2005 <>.
  7. Garrett, J.J. “An Interview with Flickr’s Eric Costello.” Adaptive Path, 4 August 2005 <>.
  8. “Using Technorati Tags.” Technorati<>.
Update :: January 22, 2020