The program for a recent presentation at my daughter's school footnoted Wikipedia for a few definitions that were supposed to provide background for whatever cultural thing the kids and we were learning about. I thought this was pretty funny, because the point of footnotes is to show that you didn't just make something up; you got it from a source that the reader can check on to follow up on the information. A source that anyone can edit, that makes the news every week for the many silly errors it has, is not a sensible thing to reference in a footnote.

Nevertheless, I use Wikipedia several times a day. I often don't get past the first few sentences of an entry, but those first few sentences can be remarkably useful, especially in certain categories:

• Geek stuff When the phone company repair guy gave us a new DSL modem, he warned me that I might need to dig up certain dialog boxes to reset some things because my new modem was a DHCP one, unlike my old Dynamic DNS one. I'd heard these acronyms before, but didn't really understand them. Wikipedia straightened me out. (Of course, if either of these entries was full of errors, I have no way of knowing this, but I'll get to that.)

• Companies This is one category where Wikipedia is often better than a more official source. A typical company's "About" web page offers a vague, buzzwordy extension of their already vague mission statement about the value-added synergy of the total solution lifecycle suite that they provide. The same company's Wikipedia page probably starts off with a brief description of what they're known for making or doing, where they're based, how long they've been around, and their stock ticker symbols. (Of course, marketing communications people know that anyone can edit a Wikipedia entry, and you can often see their footprints in a Wikipedia entry.) For example, Nike's Company Overview page doesn't mention that they're a "sports and fitness" company until the third paragraph, and even then there's nothing to distinguish them from a company that makes treadmills, skis, or lacrosse sticks, none of which they make. Their Wikipedia entry starts by saying "Nike, Inc. (Pronounced: NIGH-KEY) (NYSE: NKE) is a major American manufacturer of athletic shoes, Clothing/apparel, and sports equipment." BP's What we do page tells us that "[their] business is about finding, producing, and marketing the natural energy resources on which the modern world depends"; Wikipedia tells us that "BP plc (LSE: BP, NYSE: BP, TYO: 5051 ), originally British Petroleum, is a British energy company with headquarters in London, one of four vertically integrated private sector oil, natural gas, and petrol (gasoline) 'supermajors' in the world, along with Royal Dutch Shell, ExxonMobil and Total"—far more useful information.

• Semi-famous people You hear a name, you've heard it before, you're not sure why. If it's a musician or band, I recommend allmusic.com, but otherwise, Wikipedia will give you the general idea of why someone is famous. Jaron Lanier complained that his one short film seen by only a few people didn't qualify him as a filmmaker, so he kept removing this title from his Wikipedia entry, entry and it kept re-appearing. (As of today, it's not there.) Still, the first few sentences give a reasonable summary of why he's famous in certain circles: "Jaron Lanier (born 1960) is an American musician and virtual reality developer. He claims to have popularized the term 'Virtual Reality' (VR) in the early 1980s. At that time, he founded VPL Research, the first company to sell VR products."

• Pop culture If BoingBoing starts throwing around some Japanese word that may be a kids card game, a video game, or some sex trick, I'm usually confident that Wikipedia will tell me what that thing really is. Looking at the Lycos Top 50 list recently, I had no idea what "Naruto" at number 12 was; I just found out from Wikipedia that it's a Japanese manga comic and TV series. Number 31, "Limewire," was also a mystery to me until I found out that it's a Gnutella client. (Looking at the Lycos Top 50 just now, it seems broken; the actual list isn't showing up.)

• Area codes This is more useful to Americans and Canadians, but others interested in the three-digit numbers sometimes repeated in hip-hop songs may find it handy. If I see a phone number and have no idea where in the country it is, I'll find out from Wikipedia, and I'll probably find out much more about it. For example, see their entry for my last area code, when I was representin' the BK.

A recent New Yorker article on Wikipedia (and don't miss a recent Onion piece), which is particularly good on the project's subcultures, reminded me of something else about the quality of Wikipedia entries: the only way you know an article is really high-quality is if it's telling you things you already know. One of the first times I looked at Wikipedia, I looked at their entry for XSLT, and it was awful. Friends told me "Just fix it! That's what Wikipedia is all about!" But, this entry needed replacement, not fixing, and it felt like bad etiquette to completely throw out an entry for a basic W3C standard, so I didn't do it. Several months later, it had evolved to a more reasonable description of XSLT, so I felt comfortable making a few changes and additions—for example, adding a mention of the W3C.

These two experiences with their XSLT entry form the yin and yang of my attitude about Wikipedia, reminding me that you have to take the entries with a grain of salt, but when you do, they can be pretty useful. Like I said, for all I know, their DHCP entry could be full of technical errors. If you're doing serious research on something, Wikipedia is not a serious source, but because it may point to serious sources, it can provide a good starting point.

And for God's sake, don't footnote it.