This document provides an overview of wikis and Wikipedia. It defines wikis as websites that allow collaborative editing of content using a web browser. Wikipedia is described as the largest online encyclopedia, created using wiki software. Key aspects of wikis and Wikipedia discussed include their collaborative nature, popularity, policies around neutral point of view and verifiability of information. Usage statistics of wikis and Wikipedia are also presented.

1. Web 2.0 blog, wiki, tag, social network: what are they, how to use them and why they are important Wiki and Wikipedia

2. This material is distributed under the Creative Commons "Attribution - NonCommercial - Share Alike - 3.0", available at http://creativecommons.org/licenses/by-nc-sa/3.0/ . Part of the slides is the result of a welcome distance collaboration with prof. Roberto Polillo, University Milan Bicocca ( http://www.rpolillo.it )

3. Wiki: introduction Wikis, invented in 1995 by Ward Cunningham , have emerged as one of the simplest means to collaborate online A wiki, a term in the Hawaiian language that means "quick" or "very fast", is a web-based environment for sharing and managing documents and files where users can view and add content, but also to modify existing content posted by other users http://www.youtube.com/watch?v=-dnL00TdmLY (wiki) The term wiki also refers to the software used to create a wiki website (Wikipedia is the most famous website based on wiki technology) A wiki enables documents to be written collaboratively in a simple language using a web browser Wiki technology is the easiest way by which web pages can be created and updated

4. Email vs. Wiki collaboration

5. Wiki and wiki farms Cunningham's Top Ten Wiki Engines and Wiki Farms Wiki farms host wikis, often for free: http://en.wikipedia.org/wiki/Wiki_farm http://en.wikipedia.org/wiki/Comparison_of_wiki_farms Wikia, founded by Jimmy Wales, Wikipedia founder (2011: 165k communities hosted, 2M users, 350M pages/month)), started for free, now freemium (remove ads) http://www.wikia.com/wiki/Wikia see http://lostpedia.wikia.com/wiki/Main_Page http://uncyclopedia.wikia.com/wiki/Main_Page ;-) about 1 million wikis managed by www.wikispaces.com

6. Enterprise Wiki Wikis can be a valuable support to the work activities. So a company can acquire its own wiki platforms, providing a service wiki for use by employees The use of wikis can be a useful tool for managing business information, customers, projects and document workflow http://www.wiki.istat.it e http://wiki.istat.it http://www1.unece.org/stat/platform/display/msis/Software+Sharing http://www.essnet-portal.eu/project-information/core

7. Wikipedia: introduction Wikipedia is one of the major Web 2.0 sites Wikipedia was created in 2001 with the goal of an encyclopedia free and reliable. Jimmy Wales, founder of the project, spoke of "an effort to create and distribute a free encyclopedia of the highest possible quality to every single person on the planet in their own language." The result went beyond all expectations: Wikipedia, with over 20 million entries and 20 million registered users, is the largest collection of human knowledge. Wikipedia exists in over 280 different languages and receives over 60 million hits per day http://en.wikipedia.org/wiki/Wikipedia

8. Wikipedia: five pillars http://en.wikipedia.org/wiki/Wikipedia:Five_pillars 1: Encyclopedia - Wikipedia is an online encyclopedia 2: NPOV - Wikipedia has a neutral point of view 3: Free - Wikipedia is free content that anyone can edit and distribute 4: Code of conduct and etiquette - Wikipedians should interact in a respectful and civil manner 5: Ignore all rules - Wikipedia does not have firm rules

9. Wikipedia: Core Content Policies NPOV http://en.wikipedia.org/wiki/Wikipedia:Neutral_point_of_view Verifiability http://en.wikipedia.org/wiki/Wikipedia:Verifiability No original research http://en.wikipedia.org/wiki/Wikipedia:No_original_research Biographies of living persons http://en.wikipedia.org/wiki/Wikipedia:Biographies_of_living_persons What Wikipedia is not http://en.wikipedia.org/wiki/Wikipedia:What_Wikipedia_is_not Citing sources http://en.wikipedia.org/wiki/Wikipedia:Citing_sources

10. Wikipedia: some number

11. Wikipedia: some number http://en.wikipedia.org/wiki/Wikipedia:About http://en.wikipedia.org/wiki/Wikipedia:Size_of_Wikipedia http://en.wikipedia.org/wiki/Wikipedia:Statistics http://stats.wikimedia.org/EN/ see Comparisons In 2006 the journal Nature compared Wikipedia and the prestigious Encyclopaedia Britannica, reaching an opinion of equal authority (3.86 mistakes per article for Wikipedia, the Encyclopedia Britannica 2.92). License: started GFDL , now Creative Commons http://en.wikipedia.org/wiki/Wikipedia:Community_portal vandalism, wikilinks

12. Wikipedia: traffic R.Polillo - Ottobre 2010 www.alexa.com (Nov 2010)

13. Wikipedia: follows

14. Wikipedia: follows "The point is not that each entry is probabilistic, but that the entire encyclopedia behave probabilistic ... To put it another way, in the Britannica quality varies from, say, 5 to 9 with an average of 7. In Wikipedia ranges from 0 to 10, with an average of, say, 5. But given that Wikipedia has ten times the voices of the Britannica, you have a better chance of finding an entry on Wikipedia sensible on any topic " "What makes Wikipedia really extraordinary is the fact that improves over time: it treats itself as if its huge and growing army of workers was an immune system" "The true miracle of Wikipedia is that this system, open to contributions from non professional users, does not collapse into anarchy" C. Anderson, The Long Tail Wikipedia beneath the surface http://www.youtube.com/watch?v=QY8otRh1QPc

15. Wikipedia: follows Recent changes: http://en.wikipedia.org/w/index.php?title=Special:RecentChanges&hidebots=0&hideminor=0&hideliu=1 Who is modifying Wikipedia? (2.0 application) http://www.lkozma.net/wpv/index.html Other Wikimedia projects http://en.wikipedia.org/wiki/Wikimedia_Foundation#Projects Humour http://en.wikipedia.org/wiki/Wikipedia:Silly_Things Vandalism http://en.wikipedia.org/wiki/Wikipedia:Vandalism Wikipedia quality is not a surprise: as Eric Raymond says "given enough eyeballs, all bugs are shallow." http://en.wikipedia.org/wiki/Linus%27_Law

16. exercise 5 Test some Wiki Farm from http://en.wikipedia.org/wiki/Wiki_farm or http://c2.com/cgi/wiki?WikiFarms

17. Get familiar with Wikipedia, examining tabs “Discussion”, “Edit”, “View History”

18. Read Wikipedia page on “Wikipedia”

19. Have a look to other Wikimedia projects

20. Modify a Wikipedia page (NO vandalism! Camerino? your city? IT topics?)

21. Explore Wikia and his communities