What is WIKIPEDIA?

Ever heard about Wikipedia? It is the most popular reference site on the Web for this year! It has become the number ONE reference site on the Web, double the traffic of Dictionary.com

A search on the Wikipedia's definition resulted in almost similar writeup:

• Wikipedia is a Web-based, multi-language, free-content encyclopedia written collaboratively by volunteers and sponsored by the non-profit Wikimedia Foundation. It has editions in about 180 languages (about 100 of which are active) and contains entries on traditional encyclopedic topics and on almanac, gazetteer, and current events topics. Its purpose is to create and distribute a free, reliable encyclopedia in as many languages as possible — indeed, the largest encyclopedia in history, in terms of both breadth and depth. According to Hitwise, an online measurement company, Wikipedia is the most popular reference site on the web. (Wikipedia)

• The world's largest online encyclopedia available on the Web. Using Wiki software, Jimmy Wales started Wikipedia in 2001. By 2005, there were more than a half million entries on every conceivable subject, written by more than 16,000 contributors. Anyone can add or edit an entry. Wikipedia is widely praised for its incredible breadth, covering subjects that would never appear in any encyclopedia. There are so many "eyes" looking at an entry that erroneous information is often caught rather quickly. However, at times, Wikipedia is also disparaged because people can make edits without divulging any of their credentials or experience in the subject, as is often the case with information everywhere on the Web. (PCMag.com) (The Free Dictionary)
  

• Wikipedia is a free, open content online encyclopedia created through the collaborative effort of a community of users known as Wikipedeans. The term comes from wiki, the server program that enables anyone to edit Web site content through their Web browser. The ongoing Wikipedia project began in January of 2001, the encyclopedia offered articles in English and many in a large number of other languages. The Wikipedia Web site encourages readers to contribute to the project's development, for example by submitting needed articles or editing existing content. In addition to the encyclopedia, the non-profit Wikipedia foundation oversees several other open-content projects: Wiktionary, a dictionary and thesaurus; Wikibooks, a collection of free texts and other books; Wikiquote, a collection of quotations; Wikisource, a collection of free source documents; and Meta-Wiki, which coordinates all the other projects. (Whatis.com)

Practicality sunk in...

1. How useful of this Wikipedia to me at work and in my research?
2. Can the references used be quoted in writing, since the wikipedia content can be edited by practically everyone?
3. Any filtering systems on the controversial issues or topics published?
4. Should I encourage my students to use this reference in their works?

Solution... Need to start my personal Exploration on the Wikipedia!