1. Wiktionary – Wiktionary is a multilingual, web-based project to create a free content dictionary of all words in all languages. It is collaboratively edited via a wiki, its name is a blend of the words wiki and dictionary. It is available in 172 languages and in Simple English. Like its sister project Wikipedia, Wiktionary is run by the Wikimedia Foundation, is written collaboratively by volunteers, dubbed "Wiktionarians". Its wiki software, MediaWiki, allows almost anyone with access to the website to create and edit entries. The English Wiktionary includes a Wikisaurus of synonyms of various words. Wiktionary data are frequently used in various natural language processing tasks. Wiktionary was brought online on December 12, 2002, following a proposal by Daniel Alston and an idea by Larry Sanger, co-founder of Wikipedia. On March 28, 2004, the first non-English Wiktionaries were initiated in French and Polish. Wiktionaries in numerous other languages have since been started. Wiktionary was hosted on a temporary domain name until May 1, 2004, when it switched to the current domain name. As of November 2016, Wiktionary features over 25.9 million entries across its editions. Forty-one Wiktionary language editions now contain over 100,000 entries each. Seven of the 18 bots registered at the English Wiktionary created 163,000 of the entries there. Of the 648,970 definitions the English Wiktionary provides for 501,171 English words, 217,850 are "form of" definitions of this kind.Wiktionary – Wiktionary
2. Wikipedia community – The Wikipedia community is the community of contributors to the online encyclopedia Wikipedia. Individual contributors are known as "Wikipedians". The Oxford English Dictionary added the word "Wikipedian" in August 2012. Almost all Wikipedians are volunteers. Studies of the size of the community of Wikipedia showed an exponential growth during the early years. In April 2008, lecturer Clay Shirky and computer scientist Martin Wattenberg estimated the total time spent creating Wikipedia at roughly 100 million hours. In November 2011, there were approximately million registered user accounts across all language editions, of which around 270,000 were "active". As of today, the English Wikipedia contains an unknown number of anonymous contributors. There are 127,176 active editors on the English project. Wikipedia editors continue to increase the number, quality of the articles. A fifth spend more than three hours a day. Various studies have been done to the motivations of Wikipedia contributors. A paper written in 2005, called "Why Do People Write for Wikipedia? Incentives to Contribute to Open-Content Publishing", discussed the possible motivations of Wikipedia contributors. Oded Nov, in his 2007 paper "What Motivates Wikipedians", related the motivations of volunteers in general to the motivations of people who contribute to Wikipedia.Wikipedia community – Wikimania 2012 group photograph
3. Wiki markup – Its purpose is to be converted by wiki software into HTML, which, in turn, is served to web browsers. It was created on the original wiki site, WikiWikiWeb. There is commonly accepted standard language. Justification, keywords and so on depend on the particular wiki software used on the particular website. Different Wiki programs may support use of different sets of HTML elements within wikitext. In some cases, permitted HTML elements may be configured by individual wiki sites. MediaWiki supports many common HTML tags. There are different syntax conventions for these links. Many wikis, especially the earlier ones, used CamelCase to mark words that should be automatically linked. In MediaWiki, this convention was replaced with the notation, which Wikipedia calls "free links". Creole is an effort for a "common language to be used across different Wikis". There are several wiki engines that have implemented Creole. Version 1.0 of the specification was released in July 2007. It is not supported by MediaWiki. VisualEditor is an alternative to editing the raw wiki markup code.Wiki markup – Screenshot of the edit window in a Wikipedia article. Note the <nowiki> tag, used to escape wiki markup and HTML. HTML comments can be seen inside the <!-- --> tags.