A recent question on Stack Overflow asked why Quicksort is called Quicksort, even though it sometimes exhibits O(n2) behavior whereas Merge sort and Heap sort are both O(n * log(n)) in all cases. (For those unfamiliar with the terminology, he’s asking why it’s called “Quicksort,” when other algorithms are theoretically faster.) It’s a reasonable question for a beginner to ask.
One person commented that the answer to the question can be found in the Quicksort article on Wikipedia. But the person asking the question rejected that source because “My professor said Wikipedia is not an authentic site.”
I doubt that’s what the professor said, because a college professor telling students not to use Wikipedia would be, at best, irresponsible. I suspect that the professor said Wikipedia should not be cited as a primary source in formal writing, and the student took that to mean Wikipedia is not a reliable source of information. It seems a prevalent opinion among many. I know intelligent people who will not use Wikipedia. At all. For anything. I cannot understand that behavior.
In my experience, Wikipedia is a highly reliable source of information on fact-based topics (historical events, general science, algorithms and data structures, mathematics, astronomy, etc.), and a good introduction when it comes to political, religious, or other emotionally-charged topics. If I want to know what something is or was, then Wikipedia probably has an article about it, and that article will be accurate enough for me to get the general idea. Quickly skimming an article gives me a shallow understanding: enough that I don’t feel completely ignorant when somebody starts talking to me about the topic.
More critical reading not only supplies details, but also gives me a feel for points of controversy. Because Wikipedia articles, especially articles on current events or highly charged topics, are often edited by multiple people, it’s difficult for any single person or group to present a completely one-sided viewpoint. It’s also fairly easy to determine when a topic has been edited to remove any hint of controversy.
The best thing about Wikipedia is that it contains mostly reliable articles on almost every topic of any import. The second best thing is that those articles cite their sources. Every article has a “references” section in which it lists the sources for factual statements made in the article. If a factual statement does not have a reference, there is an annotation saying so. If the article lacks references in general, there’s a big note at the top of the article saying so.
With the references listed, one can easily spend a few minutes reading the primary source material to get more details, or to see if the article presents an accurate summation of the material. A Wikipedia article, like a well-written research paper, is verifiable. Contrast that with a printed encyclopedia, which rarely cites sources.
There are pretty high standards for Wikipedia articles, and the community of editors does a very good job of ensuring that articles meet those standards. If an article does not, there are prominent annotations in the text. If an article appears to be opinion-based, presents only one side of a controversial topic, lacks references, appears to be purely anecdotal, or runs afoul of any number of standards, there is a clearly marked indication of that in the article itself. I’ve seen things like, “this article lacks references” at the top of an article. Or “reference needed” when an unsupported assertion is made. Countless articles say, “This article does not meet standards.”
In short, a Wikipedia article gives you all the tools you need to gauge the reliability of the information presented. Certainly much more than a newspaper, television news channel, printed encyclopedia, magazine article, random Web site, your favorite politician, etc. Of those, only Wikipedia makes it a point to give you the resources you need to verify the information that’s presented.
Other than scientific journals, I can’t think of a general information source that I trust more than Wikipedia. It’s the first stop I make if I want to learn about anything.
Not that I take everything on Wikipedia as gospel. Like any other source of information, there are inadvertent mistakes and deliberate falsehoods in Wikipedia articles. But my experience has been that the number of such incidents is much smaller than in any other source of general information that I’m familiar with. More importantly, such things are typically identified and corrected very quickly.
I trust information from Wikipedia articles, but I also verify it through other means. By contrast, I’ve come to distrust information from most news sources, and use other means to determine the veracity of their articles. The primary differences here are that Wikipedia articles tell me where I can verify the information, and I’m usually able to verify it. News outlets pointedly do not reveal their sources, and very often I find that their versions of events are, to be kind, not entirely accurate.