Differences between Wikipedia, Wikimedia, MediaWiki, and wiki/es

¿Confundido sobre la diferencia entre MediaWiki, Wikimedia, Wikipedia y Wiki?

Wiki
Wiki es un término genérico que es utilizado para describir un tipo especial de sitio web colaborativo, en el que su contenido puede ser editado por cualquier visitante y/o usuario; no es un nombre propio.
 * wiki (como adjetivo) «la manera Wiki» y el antónimo no-wiki son utilizados también para describir la filosofía comunitaria (p. ej.: «Ésa no es una manera muy wiki de hacerlo»)
 * Wiki (con mayúscula) y WikiWikiWeb se usan para referirse a Portland Pattern Repository, el primer wiki creado.
 * software wiki y motor de wikis son términos que se refieren al software que impulsa los sitios web tipo wiki. Hay muchos tipos diferentes de software para wikis; algunos son bastante simples, y otros poseen características avanzadas específicas. See also: Wikipedia's entry on "wiki software" or the Portland Pattern Repository's "canonical" list of wiki engines.

For a more complete description, see Wikipedia's entry on "wiki".

Wikimedia
Wikimedia is the collective name for a group of inter-related projects, including Wikipedia, Wiktionary, Wikisource, Wikibooks, and others, which aim to use the collaborative power of the Internet, and the wiki concept, to create and share free knowledge of all kinds. Like "Wikipedia", "Wikimedia" is a trademark, and should not be used for projects which are not officially affiliated. Wikimedia is also used as a shortened form of The Wikimedia Foundation.


 * The Wikimedia Foundation is the non-profit organization which funds and manages these projects. For more information, see the Foundation's homepage
 * The term Wikimedia servers is often used, referring to the computer hardware on which all Wikimedia projects are hosted. The servers are run by employees of the Wikimedia Foundation, many of whom also work on the MediaWiki software (see below). The Wikimedia servers are not available for hosting projects not run by the Wikimedia Foundation. See also: Wikimedia servers.
 * The Wikimedia Meta-Wiki, commonly referred to as Meta, is the wiki used to discuss issues which affect all Wikimedia projects. See also: About.
 * Meta should not be confused with MetaWiki, a search engine that is not part of the Wikimedia group of projects.
 * Wikimedia Deutschland, Wikimedia Russia etc. are not part of Wikimedia Foundation, but usually are friends of it.

See also: Wikimedia, The encyclopedia article on Wikimedia.

Wikipedia
Wikipedia? Wikipedia is [//www.wikipedia.org/ Wikipedia], The Free Encyclopedia. Who doesn't know Wikipedia? ;)

MediaWiki
MediaWiki is software. The particular wiki engine developed for and used by Wikipedia and the other Wikimedia projects. It is freely available for others to use (and improve), and there are many copies in use by all sorts of projects around the world.

See also How does MediaWiki work?, Sites using MediaWiki, How to become a MediaWiki hacker.

Video

 * [//www.youtube.com/watch?v=gXD1TRGafQ0 The State of Wikipedia] on YouTube