No. A 'wiki' is any site that uses the wiki system of public creation and editing. Wikipedia is most well known site that uses this system, but that does not mean any site with 'wiki' in, is in any way related to the Wikipedia.
The most well known site using "the wiki way" is probably Wikipedia.com
You can copy Wiki content for use on your own site - BUT - you must acknowledge on your site where the information came from.
Wikipedia is a wiki because the underlying software (Mediawiki) has the features commonly associated with a wiki site. The word wiki comes from Hawaiian for quick and a wiki site allows the content to quickly change since anyone can edit it.
Wikipedia
Wiki answers... Answers.com
Yes. Wikipedia is an example of a wiki, a site that can be edited by its users.
No. This is a Wiki site not a chemist.
it's classified
I honestly do not know where to find a site on wiki cloud computing. However, if I were to guess a good spot to start would be a wiki page for the same name.
There are many Wiki websites in the world and on the web. Results show that 32% of all websites have some kind of wiki program and/or wiki website added to it.
Wiki Answer's is the best site to get information in a very fast way.