Wikipedia's content is created by its users. Because pages are continually being edited, no article is ever finished. As such, Wikipedia is subject to some unique hardships  that do not affect traditional encyclopedias. It has self-healing systems in place to deal with these challenges, and even a page designed to explain them .
One pertinent issue on Wikipedia is "vandalism": silly or offensive edits of the site's articles. For example, Sarah Lane, presenter of "Sarah's Blog Report", part of The Screen Savers TV program on TechTV, "vandalized" the Wikipedia page on monkeypox live on air  - leading to a surge of vandalism on that page by viewers of the TV show. Lane later wrote that: "Although this excites me in its ease and simplicity, it's a little frightening. I mean, what if I had instead written 'My boss is a big fat **** and his phone number is ****'? Sure, somebody would delete it, but this calls for some seriously dedicated moderators." 
"Because Wikipedia is a radically free, open project, it attracts an anarchistic element," Larry Sanger, co-founder of Wikipedia, admitted to Wired News. "Fortunately, most of us are willing to take a definite stand against vandalism ... and to get rid of it instantly."
Recent research by a team from IBM found that most vandalism suffered by Wikipedia had been repaired within five minutes. That's fast: "We were surprised at how often we found vandalism, and then surprised again at how fast it was fixed," says Martin Wattenberg, a researcher in the IBM TJ Watson Research Center, in Cambridge, Mass.
First, because there are a huge variety of participants of all ideologies and nationalities Wikipedia is committed to making its articles as unbiased as possible. There has been criticism that the systemic bias of individual participants can color the neutrality of an article. However, the aim is not to write articles from a single objective point of view — this is a common misunderstanding of the policy — but rather, to fairly present all views on an issue, attributed to their adherents in a neutral way. Of course, establishing a consensus on what views should be thus attributed can often require much (sometimes heated) discussion and debate.
Second, there are a number of article naming conventions; for example, when several names exist, the most common one in the respective Wikipedia language is preferred.
Third, Wikipedians use "talk" pages or other "out of band" methods to discuss changes to articles, rather than discussing the changes within the articles themselves. This marked a break from other wikis of the time, such as Ward Cunningham's WikiWiki.
Fourth, there are a number of kinds of entries which are generally discouraged, because they do not, strictly speaking, constitute encyclopedia articles. For example, Wikipedia entries are not dictionary definitions, and the wholesale addition of source material such as the text of laws and speeches is generally frowned upon. (However, some of Wikipedia's sister projects, such as Wiktionary and Wikisource, are designed to be repositories for many alternative forms of reference material that do not fit well into Wikipedia.)
Fifth, there are a variety of sometimes contradictory rules, guidelines, policies, and common practices that have been proposed and which have varying amounts of support within the Wikipedia community. When these proposed rules are violated, the community decides on a case-by-case basis whether they should be more strictly enforced or not.
The software that originally ran Wikipedia was UseModWiki, written by Clifford Adams ("Phase I"). At first it required CamelCase for links; soon it was also possible to use the current linking method with double brackets. In January 2002, Wikipedia began running on a PHPwiki engine, which used an underlying MySQLdatabase, added many features (and abolished the behaviour of CamelCase words automatically becoming links), and was specifically written for the Wikipedia project by Magnus Manske ("Phase II"). After a while, the site started to slow down to such an extent that editing became almost impossible. Several rounds of modifications to the software provided only temporary relief. Then Lee Daniel Crocker rewrote the software from scratch. The new version, a major improvement, has been running since July 2002. This "Phase III" software is now called MediaWiki, and is used by many other wiki projects. Brion Vibber has since taken the lead in fixing bugs and tuning the database for performance.
In late 2003, server outages began to seriously diminish the productivity of Wikipedia contributors. Many reported difficulty editing articles as a result of time-outs and severe slowness. This was due to congestion on the single server that was running all the Wikipedias at the time.
As of June 2004, the project runs on nine dedicated servers, located in Florida. This new configuration includes a single database server and four web servers, all running Redhat Linux. The web servers serve pages as requested, performing page rendering for all the Wikipedias. To increase speed further, rendered pages for anonymous users are cached in a filesystem until invalidated, allowing page rendering to be skipped entirely for most common page accesses. Cached requests are served by two Squid servers; the new servers are linked via two file system NFS servers (one primary and one backup — the primary NFS server is currently also the email server).