Bloggers and journalists are both given to making wildly inaccurate generalizations about each other, often based on a nearly total lack of experience with the others' complementary roles in informing the public.

And I've just generalized about both of them, so there!

For clarity's sake, let's define some terms. "Blogger" is easier, because it's a new word and hasn't had time to accrete a multitude of overlapping and sometimes even conflicting meanings. A "blog," clipped from "Web log," is a Web page frequently updated with the proprietor's take on - well, whatever pushes his buttons. Or hers. Or theirs; many blogs are group efforts.

Many blogs are personal diaries, but shared with the world rather than neatly written in a tiny book with a key so Mom won't read it. Others, depending on the blogger's interest, focus on public-policy issues.

The "blogosphere" -- a painfully ugly word, but it is useful -- is all the blogs together, taken collectively. What they have in common is, nothing at all.

"Journalist" is harder. For one thing, there's this amorphous entity referred to as "journalism." It can mean either what journalists do, or the institutional structures in which they do it. Oh, do let's throw caution to the hurricanes here, and coin another ugly new word; the "journosphere" is the collectivity of institutional structures.

By "journalist," I refer to someone who works in the journosphere.

That's a huge range. At newspapers, it can mean anyone from prototypical investigative reporters like Bob Woodward and Carl Bernstein of The Washington Post, who brought down an American president, to the intern who types in the high school sports scores over the weekend and dreams of being Woodstein one day. Then there are all the other kinds of print journalists, who work at small dailies or suburban shoppers, at magazines or company newsletters. And that's not even to start on the variety of other media, the wire services, radio and television, broadcast and cable and satellite, the Internet and media we've hardly thought about yet.

In that very specifically defined sense, bloggers (mostly) aren't journalists, just as most journalists don't blog.

But having been specific about those definitions, I can now be clear in saying, "journalism" means any activity commonly practiced by journalists as part of their job responsibilities.

There is no doubt that some bloggers do journalism. Ed Morrissey, Captain Ed at the blog Captain's Quarters, has at least as good a claim as The Washington Post has to bringing down a government -- the Liberals in Canada, who lost the Jan. 23 election in part because of revelations about Liberal financial scandals that were suppressed by Canadian courts and published on his blog.

Let it be true that equally stout-hearted Canadian bloggers rescue free political speech in the United States when the misbegotten McCain-Feingold law strangles it in the November elections (but that's a different crusade).

At the 'sphere level, I believe there should be little doubt, blogs and traditional media are complementary, that is, each does something easily that the other has difficulty doing at all.

On the side Advantage - Blog! there's Powerline and the 60 Minutes Wednesday program broadcast Sept. 8, 2004, based on fabricated "memos" regarding President Bush's service in the Texas Air National Guard. By early the next morning, Powerline blogger Scott Johnson -- tipped off by readers -- had picked up and publicized a post on FreeRepublic.com showing that the memos couldn't be what CBS claimed they were.

Within hours, Johnson's post (www.powerlineblog.com/archives/007760.php) had received hundreds of "trackbacks," links from other blogs that had told their readers about it. And Charles Johnson nailed Dan Rather's career coffin firmly shut with an animated post (littlegreenfootballs.com/weblog/?entry=12526_Bush_Guard_Documents_Forged) showing that CBS's supposedly 30-year-old military documents were a near-perfect match for what you'd get if you simply opened a new Microsoft Word document and started typing in the same text.

Could the traditional media have uncovered the same story? In principle, certainly. In reality, probably not. As the story unfolded in the blogosphere, dozens of people contributed information and expertise to it, sources the most diligent reporter would probably never have found, even if he'd thought to go look for them.

Who knew the Texas Air National Guard followed a stylebook that told typists how many lines they should use, and where on the page to put them, to identify a memo writer's rank and current assignment?

Well, somebody did know, but not the people who wrote the code for Microsoft Word.

On the other hand, when traditional media know where the story is, they can call on resources few bloggers will have. The Rocky Mountain News, in May, published a five-day series, "Early Exit: Denver's Graduation Gap," which explored the fact that only a third of the students who started eighth grade in Denver public schools in 1999 graduated on time in 2004.

Dozens of people worked on that series, over a period of months. They came not just from the newspaper, but also from the school district, which gave us great cooperation. Of course they included reporters and editors, but also photographers, graphic artists, page designers and a university researcher specializing in education statistics.

In principle, a dedicated blogger could have put in the equivalent of two or three years' full-time work to do the same story, but in reality, it wouldn't happen. Whatever you may believe the essential functions of journalism to be, it should be easy to agree that the capacity to cover more and different kinds of stories well enhances them.

Which 'sphere is more accurate? Neither, on balance, but they take very different approaches to errors because they are trying to survive in different environments.

For traditional media, publication is forever. Once you've put the Barbary pirates in the wrong century, as I would have done on one occasion except for the superior historical knowledge of a colleague who was reading proofs, there it is in ink on half a million sheets of newsprint, never to be recalled. Even if we make a correction at the earliest possible moment, as we would have done, it's not in the same place or for the same audience.

So most of the effort devoted to accuracy in print and broadcast media is spent getting facts right before publication. People who get stuff wrong a lot more often than average get fired a lot sooner than average. Jayson Blair was such an embarrassment to The New York Times, not because he was typical but because he was an anomaly.

Overwhelmingly, the facts are right. The Rocky obsessively tracks and corrects errors of fact, as do most newspapers of any size. In 2005, we published 577 corrections. That sounds like a lot, but we publish millions of words annually, mostly written on deadline so "fact-checking" -- a magazine term - isn't even an option.

Bloggers doing journalism, in contrast, mostly work alone. They're probably neither more nor less conscientious than journalists - how would anybody know? -- but they depend on their audience, rather than their pre-publication colleagues, to correct errors.

Either way works; you just have to be careful about what you read.

And finally, what about "bias"? Every conceivable viewpoint is available somewhere in the blogosphere, but any given blog usually has a point of view. No problem there.

What critics who rail about bias in the "mainstream media" usually forget is that the same is true of most of the journosphere as well. People read The Nation or National Review, as their fancy takes them, but don't complain about "bias" in these extremely opinionated publications.

Only a small fraction of journalists have stereotypical "just the facts," hard-news jobs, where objectivity is at least a goal, if one not always achieved. "Fair" to a news reporter doesn't mean the same thing as "fair" to an editorial writer. Sports fans don't want their favorite teams covered by earnestly objective writers. And what does "fair" even mean to the food editor? Should she give broccoli equal time with chocolate on Valentine's Day?

Journalism is a big enough job for bloggers and traditional journalists both. And it's all the better for having both of them doing it.