Wikipedia
Wikipedia is an encyclopedia wiki at [www.wikipedia.org]. A wiki is essentially a user contributed site, like this site. Wikipedia is likely the largest wiki in the world. In fact, you likely already know about it. Nevertheless, go to these Wikipedia links about wikis and Wikipedia to learn more about them generally.
Caveats and uses
Two caveats about using Wikipedia, YMMV on any particular subject (especially after factoring the degree to which it is of interest to contributors), and the grain of salt rule (see below).
As far as the uses that Wikipedia has for Ars Magica games, there is a lot. It is a very good starting point for any research. You should be able to find articles or pages on any country or region of interest to your saga, as well as well known, and even not so well known, historical figures. Articles on questionably real people and utterly fictitious people can also be found, the more famous (such as King Arthur, Merlin, or Baba Yaga), the more likely they will have an article or at least be included in an article on a larger subject, like regional mythology. So you can get both what the modern understanding or belief about the "real history" of subjects and, at times, how they were viewed at the time.
Now an even half way decent article will also cite sources for whatever is written in the article, or at the very least, give some references that you can look up independently. And there is the second great use for Wikipedia, a good way to track down other sources on a subject.
Finally, if you are looking up the article on a public domain work, more often than not, one of the external links on Wikipedia will lead to a free copy of the work.
The grain of salt
As a wiki, the articles in Wikipedia are only as good as the contributors who take an interest in them. What's referred to as vandalism- a term that cover simply writing stupid things in the article to erasing large portions of the article and deliberately putting false information in the article- can occur. The more contributors there are to an article, the less likely you will find this happening. Nevertheless, there are number of reasons why this won't be too much of a problem.
- Wikipedia, like the Project Redcap wiki, keeps a history of all changes, so you can always look back some to see if any radical changes have been done.
- Most vandalism won't remove sources, so those usually remain.
- You can check back after a while to see if any corrections have been made.
- You may be able to check an article about the subject in another language (see below).
- Finally, if some false information is put in, but it still works for your Saga, no loss. Of course, most people would prefer to knowingly deviate from the real history or material, but in that case, simply use due diligence in checking on what's claimed in the article, including some of the ideas presented in these points.
Non-English language articles
The English Wikipedia has the most articles (over 4,850,000 at the time of the creation of this page about Wikipedia). But the major European languages, as well as Vietnamese and two languages from the Phillipines (Sinugboanong Binisaya and Winaray) have over 1,000,000 articles each. Chinese and Japanese each have over 800,000 articles and even Latin has over 100,000.
With free translation sites like Google Translate you can read articles in other sites. YMMV, but usually you can get basic idea, at least. Google Translate can also translate .pdfs of the right sort (if they are from scanned documents, they would have had to undergone an ocr process).
Trivia
Yep, Ars Magica does have it's own article in Wikipedia, here. For those already playing, there shouldn't be too much useful there. If you contribute to the page, keep in mind that Wikipedia operates under a Creative Commons License. Try not put overly much from copyrighted material of Atlas Games or others.
See also
- TV Tropes, another large wiki dedicated to tropes- conventions of various media used to tell stories- and the media that use them. These can be of great help, both from reviewing a trope directly or seeing examples of where it's been used ("you know how in that one scene they..."). Check out the write up on TV Tropes in our wiki for more on how it can be used and warnings on how it can be a HUGE time suck.