Wiktionary:Welcome, newcomers
Hello and welcome to Wiktionary. Wiktionary is a free dictionary and thesaurus that's being written collaboratively on this web site. Anybody can edit any article, and a record of changes is kept. Since December, 2002, we have created about 6,994,536 articles, so we've made some progress (well we got it set up at any rate!).
Ordinary smart people, like you, are building this project very actively; as you are reading this, someone is probably editing an article. There are a lot of Ph.D.s and graduate students and other very smart and knowledgeable people at work here-- but everyone is welcome. You don't even have to be logged in to contribute, but we'd like to know who you are. Anyway, you can just dive right in and work on any page you like. Please drop in as often as you can. If you're the kind of person that many of us are, you'll soon be addicted to the "Recent Changes" page. You can (and should) be bold in updating pages. And above all, play nice.
One of the most important things you should know is that we (the existing community) have established some cultural norms that you should respect. We try not to argue pointlessly. This isn't a debate forum. After civilized and reasonable discussion, we try to reach a broad consensus about what entries should say to accurately present neutral summaries of all relevant facts for future readers. We try to make the entries as unbiased as we can, which means that the articles, even on controversial topics, are not meant to be platforms for preaching of any kind. Bear in mind that this is an encyclopedia, which means there are many things that it is not. If you feel uncomfortable with making changes to someone else's work, and you want to add your thoughts, questions or comments about an article, the place to do that is the article's talk page (click on the 'Talk page' link in the sidebar or at the bottom of the article). Again, though, we generally try to avoid discussion for its own sake. There are also some other community norms codified via some links listed below, particularly Wiktionary policy. And, you might want to review the most common Wiktionary faux pas.
Humor in definitions is fine and can make this project more fun and more readable. But this is intended to become an important basic resource on a particular area of human knowledge, so please don't treat it as a big joke. Entries should be lively and readable, and they should also explain things as clearly as possible.
You might expect Wiktionary to be a low-quality product because it's open to everyone. But, perhaps it's the fact that it is open to everyone that has the potential to make a lot of these definitions pretty good, and ever-improving. To alter a now-famous catchphrase: "Given enough eyeballs, all errors are shallow." We tend to cater to the highest common denominator--"lower denominators" tend politely not to touch articles they know nothing about! We hope you have fun. If you're intrigued by the idea but you have objections, see our replies to common objections.
Many Wiktionauts may also be Wikipedians
There is more introductory information: