Image: Lou Beach

It's the nature of Internet manias: they tend to leave almost as fast as they come, with only the rarest of rages sticking around for the long haul. Of the Internet “in things” that have remained “in,” perhaps the most surprising is the humble Web log, or blog. This is a kind of digital diary, a Web page to which a writer posts chronological entries on a particular topic. The main difference between a blog and a regular Web site is that the blog's information is updated frequently, often several times a day or more.

No one knows how many blogs exist, but a search of the Whois database returns over 20 000 domain names that include the word “blog.” A recent survey by Perseus Development Corp., in Braintree, Mass., estimated that there are over 4.1 million blogs just on blog-hosting sites such as LiveJournal and BlogCity. It's likely that there are at least as many stand-alone blogs. The Perseus survey also showed that about two-thirds of the blogs hadn't been updated in over two months, so the total number of active bloggers is probably somewhat less than three million.

That so few blogs remain active highlights an undeniable fact of blogging life: it's difficult and time-consuming to keep a blog fresh with constant new entries (called blog blurbs). Yet blogs of all stripes still spring up every day like so many mushrooms after a spring rain. So most blogs may be transitory, but the collection of blogs—called variously blogistan, the blogverse, or, most often, the blogosphere—remains vibrant.

Bloggers tend to be passionate about their hobby, and the best among them — the so-called blogerati or blognoscenti — are genuine stars, with dedicated followers. These include the likes of writer Doc Searles (doc.weblogs.com), the Electronic Frontier Foundation's Cory Doctorow (boingboing.net), journalist Andrew Sullivan (www.andrewsullivan.com), and technoguru Esther Dyson (release4.blogspot.com).

The vast majority of blogs are nothing more than ever-so-slightly glorified online diaries that record the daily trials and tribulations of the blogger. The worst of these journal blogs are dismissed as kittyblogs (since so many of them describe what their cat has done that day) or bloggerel (blog doggerel), and these bloggers are often accused of oversharing (providing too much detail about their personal lives) or being guilty of blogorrhea (posting too much information in general).

The rest of the blogosphere consists mostly of blogs devoted to specific topics. For example, a blawg is related to legal matters or is written by a lawyer; a bleg is used to beg for help or money; an advocacy blog supports a political cause; and a news blog or pundit blog examines mainstream news media and punditry (not to be confused with a blog that breaks its own news, or blews).

Covering language and linguistics is the job of a linguablog; a tech blog focuses on technology; an edu-blog discusses education issues; a warblog tackles war, particularly the war on terrorism; and a photog is a blog that posts pictures, particularly candid shots of people in public places.

In recent months, we've seen the rise of the moblog, a blog maintained and updated using a mobile device such as a notebook, a palmtop computer, or a cellphone. (Photogs are often updated via the new camera phones that are the latest rage.) With its emphasis on mobility, the moblog has created an interesting new dynamic at conferences and business meetings, as bloggers post critiques of the current speaker and other attendees read those critiques and comment on them. This generates an entire back channel of communication that the speaker is likely to be unaware of.

Proof, perhaps, of blogging's having arrived is the increasing roster of professional journalists who maintain blogs. These include the aforementioned Sullivan; Dan Gillmor (weblog.siliconvalley.com/column/dangillmor/), the technology columnist of the San Jose Mercury News; and Daniel Weintraub, a columnist at the Sacramento Bee (www.sacbee.com/static/weblogs/insider/).

But many blog enthusiasts scoff at these relics from the ancient media and extol the virtues of the bloggers who remain independent and free from corporate fetters. They claim these pure bloggers are the ones who will let freedom ring in the 21st century and who will light the path to truth and justice. Some dismiss this as mere blog triumphalism, but surely three million bloggers can't all be wrong?

Technically Speaking is a commentary on new words that arise in technical culture and communications. Readers are invited to respond to IEEE Spectrum at techspkg@ieee.org.