Ordinary people are everywhere. Everywhere in the media, that is - from Helen in Big Brother and reviews by email@example.com  to the man on the poster who's just bought his schoolboy hero's cricket bat because he uses a particular brand of Isa. The media are hungry to pull consumers into the production of media output. Their "ordinariness" makes them the centre of attention.
Strange, then, that every time the legendary Chicago journalist Studs Terkel has a new book published, the profiles that mark its imminent arrival speak in reverent tones about his unique ability to give voice to, well, ordinary people. "Singing the unsung hero", "Everybody who's nobody", "The man who interviews America" are typical of the review headlines. But how can he be the man who interviews America, when America, like everywhere else, is being interviewed all the time?
The answer is that Studs Terkel's interviews are different. In contrast to the traumatised first reactions, the polished soundbites and the confessional outpourings that fill the ether, Terkel uses the classic devices of oral history. He talks to his subjects about their lives, usually over several sittings, listens intently to their answers, transcribes the conversations, edits out his own questions and then often changes the people's names before publication. In his own words: "It's got to be the person's truth, highlighted."
In a world of multimedia sophistication, it seems quaintly old-fashioned. Yet the reality is that life stories, told straight and at length from the mouths of people who aren't momentarily famous - or weird - still seem pretty rare. And radical, too. Terkel's collections of interviews - Hard Times, about the Depression, Race and The Good War, about America in the Second World War (which won a Pulitzer Prize) - make one thing clear: despite the democratic truism that all opinions are as valid as others, many voices are still not listened to unless they are focus-grouping, performing or bystanding. In Terkel's books, the story is not the story; the story is the people.
Ever since Henry Mayhew published the first volume of his ground-breaking London Labour and the London Poor in 1851, the idea of listening to the unheard has remained a powerful engine of oral history. Mayhew walked the East End and made an encyclopaedic survey of the destitute and unemployed. His detailed findings and the stories he recounted shocked mid-Victorian society, which preferred to talk in the most general of terms about an impersonal and faceless mass: "the poor".
The power of oral history ever since has been that it has sought to bring to life subjects that are taboo and voices that have been ignored. It is no surprise that Terkel cites Mayhew as one of his heroes. His forthcoming book, Will the Circle be Unbroken?, is a series of conversations about one of our enduringly sensitive subjects - death. For all our media exposure, our open-mindedness and freedom of expression, the success of Terkel's books suggests that we still have not worked out how to bring wider exposure to experience that is individual and unique but, by historical or journalistic standards, unexceptional.
It is noticeable how many of the newspaper features on the tragically astounding events of 11 September were based around the unaccompanied words of those involved. Diary pieces, extended vox pops and streams of consciousness were all used. It is as if journalists realised that their copy would somehow intrude on the true teller of the story.
Terkel and his fellow oral historians have for years been employing exactly the same principles in their efforts to chronicle the shape of the everyday, not the exceptional. One of Terkel's most successful and best-known books, Working, first published in 1974, came from hearing about experiences of working life from shop floor to boardroom. Superficially, no topic of conversation could be more routine or mundane. In practice, getting people to talk frankly about their jobs has the air of subversion: the manager who confesses that he only pretends to believe the company philosophy; the politically incorrect thoughts of the gasman. Working now features on school curricula in the US.
In television and radio documentary-making, there is a superficial sense that, today, oral history is all around us. It got a particular boost at the time of the millennium epics, when the BBC brought us People's Century on screen and The Century Speaks on radio. The eyewitness is currently an essential component of the standard 20th-century historical documentary - and is used to brilliant effect by such television film-makers as Steve Humphries and Laurence Rees. And Video Diaries created a more up-to-date snapshot of the nation.
However, the vast majority of oral testimony is an illu- strative accompaniment to bigger narratives, rather than centre stage. How often are people interviewed for documentaries (I know because I have been guilty of it myself) because they prove some point or show how something was experienced, rather than just asked - with no preconception - what it was like? If the answer is unwieldy, or does not fit into the preconceived narrative of the bigger picture, well, then it often (not through malice) slips out of the final programme.
Even more dubious is the fashion for using oral testimony as a form of authenticity to enhance fictional productions. Steven Spielberg has been particularly keen to do this, inserting interviews with former GIs into his production Band of Brothers. Their essential role is to verify that this is a true story - not to offer the detail of their experience.
There is no doubt that Terkel's own popular version of oral history can have a "folksy" feel to it, in our age of postmodern marketing categorisation. His strong belief in the universality of human experience leads him very deliberately to mix celebrities and ordinary Joes, elite and blue collar. Typically, in his forthcoming Will the Circle Be Unbroken?, the words of the celebrated author Kurt Vonnegut appear alongside those of Rick Rundle, an unknown city sanitation worker. Terkel's approach was formed in the 1930s and 1940s, when progressive unity was the watchword of the Popular Front. There is a romantic simplicity to this sociology which, under current conditions, verges on the sentimental.
But oral history can be far subtler. Britain's own answer to the Chicago talker, the late Tony Parker (the man who Terkelled Terkel and wrote his biography), spent much of his career in oral history, like Henry Mayhew, dealing with crime, criminals and the dispossessed. Parker's The People of Providence, a series of personal stories from a housing estate in south London, has nothing less than the quality of a novel. The vignettes of life in a place that, to the outsider, might look lifeless give a vivacity that would be unrepeatable in any conventional exercise in journalism or social history.
It is also a technique noticeable in widely read and recent works of sociology, such as Richard Sennett's study of the new working environment, The Corrosion of Character. At that book's core are personal stories about life in the deregulated jobs market of hi-tech industries. Amid the coldness of objective indicators, market testing and quarterly targets, oral testimony can reclaim for sociologists aspects of the qualitative assessment of modern life.
And this is perhaps one of the most important dimensions of Terkel's collections of interviews. They give the lie to our inability to get beyond the anonymous babble of modern communications. Intimacy is their outstanding characteristic. It is a quality that perhaps stems from Terkel's training as a journalist: "I came out of radio, not writing. That is important." And he talked to the high- and low-born on his daily show on WMFT Chicago for 45 years. The best of radio interviewing has an intimacy and closeness to its subjects to which oral history also aspires. It is as if the simplicity of radio means that the medium can be wished out of the way to reveal the unadorned voice, and the experience it relays. Naturally, it is an illusion to think that we can somehow listen to other people free of intervention from technology - but it is a worthy ideal. As Lord Reith hoped, all those years ago, for his new invention the BBC: "Nation shall speak unto nation."
Terkel does not set himself up as "anti-media" - but one cannot help feeling that his work produces that impression. He is about as starry as oral historians get; even so, he comes across as a subtle enabler, like a documentary producer whose presence is invisible but constant. He is the opposite of the ego-historians who stalk our bookshops pronouncing on world events, and who dwarf the poor souls who are the subjects of their studies. After all, none of these books is entitled Studs Terkel on . . .
Today, at the age of almost 90, Terkel claims to have conducted 9,000 interviews and, in his semi-retirement, spends time at the Chicago Historical Society cataloguing them.
It is far too easy to believe that the lines between recording equipment and subject are now so blurred that we are all enmeshed in the ubiquitous media world. It gives the false impression that we all have equal access to the means of registering our experience. Digital technology may yet bring that. While Terkel's method of research - an old tape recorder that he's not quite mastered - does have an outdated feel, the spirit of the exercise - "personal truth, highlighted" - remains as valid, and sometimes as unreachable, as ever.
Will the Circle be Unbroken? is published by Granta (£15)
Matthew Dodd is a producer on Radio 3's Night Waves