There was an unfamiliar byline on a story out of Baghdad published in my morning newspaper last week: "Tod Robberson, Washington Post Foreign Service." Was this a new military correspondent or Middle East specialist whose appointment had escaped general notice? Was he a "stringer" or "free lancer" who had pitched up in Baghdad in search of fame, glory or permanent employment? My memory machine drew blanks. That is not altogether surprising; for lack of spare parts it has been operating recently at less than optimum efficiency on both odd- and even-numbered days.

A colleague relieved my befuddlement. Unlike our troops in the Gulf, Post correspondents have been rotated frequently during the unpleasantness with Iraq. Mr. Robberson, a new editing recruit on the foreign desk, is taking a place in the rotation.

But that tells the reader of the byline nothing substantive. What qualifies Mr. Robberson for such an assignment? Is he schooled in Middle East affairs? Had he set foot in the region before his arrival in Baghdad? Does he speak Arabic, or is he dependent on local translators of questionable reliability and loyalty? Is he a competent reporter and writer? Has he ever met a deadline?

I discovered, belatedly, that he has all the correct credentials. He is an Arabic speaker with a graduate degree in Middle East studies and with journalistic experience in Beirut, Syria and Iraq as a correspondent for the Reuters news agency.

You now know more about Mr. Robberson than you know about the vast majority of writers and commentators who deliver and explain to us each day their versions of "reality" and their perceptions of the "news." A few of them have achieved a measure of celebrity and are thus "known" to us in the way Peggy Noonan once described knowledge in Washington: "You know him. You saw him on C-Span." Other journalists -- quite a number of them -- are "known" to the small constituencies with which they are involved: the city hall crowd, the Pentagon, the politicians on Capitol Hill or in the White House, the diplomatic community, the environmentalist industry and so on. But to the ordinary reader we are not even shadowy figures. Our bylines reveal nothing. Our anonymity is complete as a bylined friend discovered after retirement a few years ago. "I have found," he said, "that I am not a has-been; I am a never-was."

If bylines do not establish our identities, what is their purpose, their utility? The American press got along without them for more than two centuries on the theory that the nagging voice you got with your morning coffee was not that of John Jones of The Bugle but was rather the institutional voice of The Bugle itself. That is the case today with editorials; they are not signed because the editorial is intended as a corporate rather than an individual expression of opinion.

Bylines came into scattered use in the news columns in the 1920s on stories written in the first person. The practice spread, in part to distinguish a "subjective" from an "objective" account of events and, in part, in recognition of the rising status of the journalist. In the 1950s and 1960s bylines were awarded to a paper's leading writers or were attached to stories as a psychic reward for a specific job well-done.

Today the byline has lost that distinction. It is attached routinely to anything longer than seven or eight inches that comes out of the word processor; it passes before the eyes of most readers with the same impact as a credit line in a TV trailer.

Still, bylines satisfy reportorial egos and impress (especially the first ones) moms, dads and our fourth-grade teachers. They also have, one of my colleagues suggests, practical utility. They are a form of advertising designed to elicit the interest of potential sources. They can be used as management tools for the measurement of productivity: How many stories did you write this year? Their use or non-use may serve a propaganda purpose: reporters occasionally withhold their bylines en masse as a bargaining tactic in labor negotiations. And within the journalism fraternity, bylines and datelines often signal promotions, demotions and departures.

But the person behind the byline is rarely revealed to our consumers. As with a choir, sopranos and tenors come and go but the collective voice is essentially the same. It is not my voice or the voice of Tod Robberson. It is the institutional voice of The Post.