It's difficult to imagine the relatively civilised, slightly worn corridors of London's old Broadcasting House, headquarters of the BBC, as being the frontline in a war. No trenches; no barbed wire; not a sign of battle-fatigue to be seen … Yet here whizz-bangs are almost as frequent as they were at the Somme. For frontline this indeed is; a place where battle-royal is pitched between the opposing camps of linguistic orthodoxy and originality. The spot where, like a pair of weirdly-named opponents from Gulliver's Travels, the Descriptivists do battle with the Prescriptivists.

Broadcasting, you see, is very much a thing of now. Even when it's not live, it affects to be conversational, matey even – entertaining and companionable. It's as true on television as it is on radio; yet because radio arrows in directly to the brain and the heart, untroubled by the distraction of image, it's on the senior medium that the voice-in-your-ear or on your shoulder is most familiarly sensed. This is where we feel we're being spoken to by our friend behind the loudspeaker grille or in our headphones as we make our way through rush-hour traffic. And when we hear something that for some reason offends, it offends deep. Er, deeply. No, hell, I mean deep.

For those who like their spoken English just-so, this tone of friendly, loose-limbed communication can cause almost continuous offence. Because, the fact is, the joy of broadcasting is that it isn't bound by rules of grammar. Sentences can be one word long. Really. In fact, the distinguished, and sadly now dead, Radio 2 music broadcaster Hubert Gregg's scripts were a welter of dot-dot-dots and stray nouns and adjectives: ‘Hello … again … from me. And tonight … in somewhat … er … skittish mood: Noel Coward …’ His broadcast style was – to use the jargon – ‘relaxed’; that's to say informal, and untroubled by the rigours of literary or academic ‘correctness’. Yet Hubert was absolutely a ‘gent’, an old-fashioned kind of chap, who'd have been deeply offended had anyone accused him of being anything but utterly proper.

So here's the paradox. Broadcasting tries its utmost to sound like its listeners yet, in so doing, offers a nightmare for linguistic purists, and the perfect hunting-ground for the solecisms that fuel their pedantry.

‘Thank goodness,’ sighed Michael Green, erstwhile eminent and deeply-respected Controller of Radio 4 back at the start of the 1990s, ‘you'll relieve me of having to reply to all those letters!’ Frank Delaney, writer and broadcaster, had approached Michael with the idea for a new programme for his network, about language. Michael had been feeling the heat from his listeners over a number of months as he undertook the Herculean task of wrenching the network ever-so slowly from the staid world of the old Home Service where it still dwelt, largely unaltered, into the era of Spitting Image and Maggie's Militant Tendency. Radio 4 would never be the same again, thank heavens, and the letters and threats from the offended many were piling up in Broadcasting House. So anything to relieve the pressure.

Thus Word of Mouth was born: the perfect theatre for language battles. And to this day, the programme still stages contests between Descriptivists and Prescriptivists – they were at it again back in April. They will, of course, never call a truce, because the Prescriptivists know they're right: good grammar is the product of centuries of careful study and has long been enshrined in the principles of Fowler's Modern Usage and in the thousands of well-thumbed English grammar books that educated an Empire. It's right, and we know it is. Split infiinitives (Star Trek was only ever a passing phase) and disinterested deployed where uninterested is meant, decimated used ‘incorrectly’ to mean devastated … the examples are familiar and (frankly) boring.

Yet even the most progressive Descriptivist – and I admit that I, for all the time I edited Word of Mouth, was one – can sometimes find her or himself blenching at the occasional ‘misplaced’ term, Malapropism or (I'd say overly) fashionable pronunciation. My own bugbear? Leverage, as in ‘this enabled the bank to leverage even bigger loans,’ where the word is pronounced levver-idge, to rhyme with Dame Edna Evver-idge … We who love language know that Americans remove a tire with a tire-lever (rhymed with never, clever, and bever-age). So ‘levverage’ isn't daft at all. For them. Yet we Brits deal with a puncture using a tyre-lever (rhymed with fever, beaver and reiver). I didn't mind so much when UK usage of the US pronunciation was restricted to the financial application, as the roots of the financial crisis, which ushered in the widespread currency of the term, were Stateside. However when I heard earnest politicians on Newsnight subconsciously, I'm sure, attempting to sound vogueish by saying things like ‘this will give the Prime Minister levverage over his cabinet …’ I felt betrayed, angry and ready to submit my own application form to join the Green-Ink Brigade.

In short, language on air is a contentious business. And thus a richly rewarding one for the broadcasters themselves. For every letter of protestation, there's an interesting programme item to be concocted. On Word of Mouth, we used to run a feature we called ‘Word of the Week’ which picked up the tenor of current discourse – in the street and on the media – to focus on the etymology, and changing meaning of words that were dans le vent like – well – leverage.

But words and language have long been a staple of the BBC's programming. As early as the 1920s M. Stéphan became something of a minor star in the nascent radio service of the British Broadcasting Company with his lessons in French. (Then again, they also broadcast instruction in ballroom-dancing … and who said conjuring on radio was daft?) In radio's heyday, too, language was to the fore on The Brains Trust, where Professor C.E.M. Joad became a star with his nuanced definitions and pernickety manner – ‘it depends what you mean by …’ was his catchphrase.

Older readers will remember, too, the radio panel game from the 1950s, called My Word!, ‘a word game,’ as Tony Shryane, its creator (and longtime producer of The Archers) described it, ‘played by people whose business is words’. It ran for over 30 years and, each week, Jack Longland (moonlighting from his day-job as Director of Education for Derbyshire) would pose questions about the English language of his panel of E. Arnot Robertson, Nancy Spain and the comedy-writing duo Frank Muir and Denis Norden. The Home Service took its fun very seriously, so the teams were first asked to define relatively obscure terms such as kumquat, dimity, curricle, vetch, frugivorous and sorghum …

Here was prescriptivist Heaven. Clarity, precision and a sense of the old unchallenged order of grammar-guides and authoritative correctness, delivered by well-educated, RP-accented people; and overseen by, for goodness’ sake, a Director of Education!

What, would ask the ever-grave Longland next, was the origin of the following expressions: to nail to the counter, let the cat out of the bag, ring the changes and lock, stock and barrel? Again, answers were serious, though the comics would constantly try to disrupt the linguistic precision with an appropriate gag. Indeed, amid all the prescriptivist exactness, humour always won the day as team-comedians Muir and Norden would offer their own wildly fantastical saloon-bar stories to ‘explain’ the origin of quotations like she stoops to conquer or a thing of beauty is a joy for ever, which the comics would each week twist into suitably barmy phrases (the latter became at the end of the story ‘a thing of pewter is a jar for ever.’) Many of the cast may have changed over the years, but Muir and Norden and their wordplay stayed to the bitter end.

While My Word! was occupying the gentler comedic corners of the Home Service and Radio 4 from 1956 to the end of the 1980s, a little factual programme became an unexpected hit for the network in the early 1960s. It wasn't a language programme per se, yet words and their (mis)interpretation were at its heart. It was conducted with brilliant understatement by the great Harold Williamson and was called Children Talking. And that's just what it was – children, talking about everything under the sun: birth, death, heaven, hell … their pets and their families. And, of course, doing so with charm, linguistic misprision and unintended humour. ‘Where do babies come from’, asked Williamson: ‘from a shop, for a shilling,’ comes the reply; ‘on an aeroplane from Heaven’; ‘you can have a baby if you eat carrots and vegetables mixed with gravy every day …’ So successful were Williamson's wondrous encounters with children they even issued an LP of them.

‘Ey, Simon! You do work me hard!’ The words were those of one of radio's greatest champions of language, Stanley Ellis, whose tireless labours for Harold Orton's great Survey of English Dialects gave him not only a unique insight into the way ordinary people spoke back in the 1950s and 60s but also tutored him in the subtle art of encouraging people to talk, and talk fluently about their lives in front of a microphone. Stanley Ellis was hard at work gathering the essential and brilliant original recordings for the SED while Harold Williamson was carving out his early career as a reporter – and they both came from corners of England rich in character and humour – Williamson from Tyneside and Ellis from Yorkshire. I think this was fundamental to their becoming utterly matchless broadcasters.

Stanley's work I knew well because, although our paths didn't cross during his fieldwork days, I listened attentively to his many contributions to Radio 4 about dialect; and when, in the early 1980s, he approached me with the idea of using those wonderful SED recordings (now safely stored in the BBC archive and at the British Library) for a new programme, I sensed immediately the potential to celebrate the richness of regional language in Britain. Stanley wanted to build his shows round the recordings he'd made thirty years earlier, but I was more interested in discovering how local language had evolved. So we used those classic SED documents as a starting point, but set out to discover people who spoke broadly today. We started work in Stanley's native Yorkshire, and progressed, through several six-part series, to chart the local speech of Wales, the West Country, the coalfields of the Midlands, Belfast, the Thames Valley and urban Glasgow … Talk of the Town, Talk of the Country was what we called the project, and stories were at its heart just as they had been in Children Talking, but recounted by men, women and children in the broadest accents and using as many dialectal terms as they could muster.

Stanley and I would sweep across the country mopping up three programmes or more in a jumbo recording trip (whence his lamentation about hard work). TOTT, TOTC, as I came to know it, was sheer pleasure from start to finish – the stories were of real, often hard, lives lived in fascinating corners of Britain, frequently those neglected by news, and all interpreted, quite naturally and unforcedly, through rich local talk. Stanley would add linguistic rigour to the narrative, pinpointing the Old Norse root of a particular dialect term or an isogloss that passed nearby that divided a trilled from a uvular ‘r’. But in the great language trench war, this was unremittingly descriptivist. No one was around to ‘correct’ Bristolian Pat Dallimore as she peppered her glorious narrative with hanging ‘l's in time-honoured local fashion (‘I went to the opera'l, and the opera'l was Tosca'l – isn't that the opera'l where she throws ‘erself off of the battuhments?’).

Yet with local accents today flourishing and perfectly accepted on the BBC as never before (Radio 4 has a particularly rich range these days), it seems almost otiose to observe that it was not always so. When Yorkshire entertainer Wilfred Pickles was asked to read the news during World War 2, as a way of offering ‘authenticity’ and distinctiveness to separate the sound of the BBC from the largely RP tones of the subversive William Joyce (‘Lord Haw-Haw’), it didn't go down well; the news needed to be pukka, delivered without accent and without inflexion. Correctness was crucial and Pickles was dropped.

When Frank Delaney and I responded to the Controller's imprecation to save him from the constant flow of letters (no emails then) about linguistic solecisms, we did so with pleasure and with open minds. It was the sort of challenge we relished, and we made a point of regularly covering the debate between prescription and description on Word of Mouth. Whether it was the Queen's English Society, or the Campaign for Plain English, we talked to them all. But given that the programme took its cue routinely from the daily agenda – we liked to reflect linguistically on current topics (discussing ‘the language of diplomacy’, for example, when some major international negotiation was in play) – the programme tended more to describe trends in language rather than prescribe how it should be spoken.

It seemed to do the trick, though, and listeners’ gripes were assuaged. Unsurprisingly, Word of Mouth continues to thrive, under the watchful guidance of Michael Rosen, 23 years on.

The appetite amongst BBC listeners for language-related programmes is almost limitless, it seems. Just a few months ago, Radio 4's news programmes were buoyed along for weeks with a pretend ‘spat’ about prescription between Melvyn Bragg and John Humphrys. Again, the ‘AI's (Appreciation Indices) that measure how well people have enjoyed different radio programmes always seem to rocket when someone like Stephen Fry tackles language on the network – he was an early and much admired guest on Word of Mouth and his Fry's English Delight today brings regular jollity and precision to the nuances of language. A few years ago, too, BBC2 mounted a brave attempt to put language front and centre on television with Victoria Coren's Balderdash and Piffle.

But for me, the two biggest and most important statements about language that the BBC has undertaken in the past fifteen years have been a pair of major radio events. To greet the new millennium, Melvyn Bragg presented The Routes of English, a history of one thousand years of the spoken language from Aelfric's Colloquy to the present day. And although that famous manuscript was the series’ outer time-limit and first central text, the programmes began where Melvyn Bragg was born: Wigton in Cumbria. ‘The place just intoxicates me all the time. It was a curious time through the war and just after the war; there seemed to be everything that anybody could want in Wigton – a lot if youth clubs, all sorts of people. There was a gypsy camp, too, and there were the fair people. We spoke a language which was very particular to this town. It was a thick Cumbrian dialect, full of Viking words, ower yonder, yet, yak, yam, that sort of thing. It had Romany words, it had Norse words, it had Indian words … and people liked to speak broad.’

The Routes of English pulsed with this kind of energy – our speakers all were passionate enthusiasts – and even the old texts we also had to deal with, because they enshrined as far as they could the spoken language, vernacular English, they too had a vigour and colour that simple written texts don't always possess. Take Aelfric. The monk wrote his famous dialogue in Anglo Saxon around the first millennium, and although it's now a thousand years old, it still speaks to us as vibrantly and directly as when it was written. And while it is, of course, in fact a piece of written text, this sequence of rather formalised ‘conversations’ between a teacher and his pupils, an oxherd, a ploughman, a huntsman, fisherman, merchant and so on has the same sort of colourful vigour as do those wonderful images of medieval country life contained in the margins of the British Library's celebrated Luttrell Psalter. Here's the opening:

So, you see, even as far back as the dawn of our language, the Prescriptivists were making their influence felt: ‘how to speak properly’; ‘we are ignorant and badly spoken’. Although they don't often refer to them in these terms, the people who complain about the ‘declining standards’ and ‘dumbing down of language on the BBC’ are referring, just as Aelfric's pupils were, to ‘meaningless base words’. Old concerns run very deep indeed.

We followed the first run of Routes with further series about the English language overseas, in America and the West Indies, in South Africa and India and Australia. We looked again at dialect too, which allowed us to be more systematic than Stanley Ellis and I had been a dozen years earlier, examining the way five different dialects sprang directly from their linguistic and cultural roots. The success of The Routes of English prompted Melvyn to turn the series into eight striking television films, though not for the BBC. Many of the stars of Routes, such as the medievalist Dr Katie Lowe, turned up again in his Adventure of English for ITV. But for my money, while the television programmes had the budgets and exotic images to colour in the backdrops to the words, the radio series had the edge in both liveliness and depth.

Five years after the first series of Routes, the BBC mounted its biggest celebration of contemporary speech yet, and it's something that will, I suspect, never be repeated. It was very costly – at least in terms of radio budgets – and it embraced the whole of BBC local radio, almost all the national radio networks as well as BBC1 and BBC2 television. It was called Voices and it was the brainchild of a producer in BBC Wales and a pioneering BBC local radio manager. I got involved too at an early stage, and together we brought together a task force of ‘audio-gatherers’ from dozens of local radio stations. These interviewers were dispatched into their communities to talk with men, women and children organised in discrete interest groups – taxi-drivers, crane-drivers, bus-drivers, dockers, habitués of a gay bar or historic battle re-creationists … the list was wide and deep, and spread across over 320 separate UK locations.

At Leeds University, English language researchers assembled a clever questionnaire that gave the interviewers a series of prompts to introduce certain areas of interest into the conversation. Initially, most of the gatherers would ask the participants about their lives in general terms, and then move on to carefully selected word prompts designed to elicit known specific and indicative regional variation in terminology – the local terms for sofa, soft shoes, playing truant, the lavatory, the alleyway beside a house, a flashily dressed young man and so on were well known to vary widely across the UK.

At the same time, these prompts produced wonderful anecdotage, just as 20 years previously, Stanley Ellis's Talk of the Town series had: the tales of midnight excursions to outside water-closets and the mishaps involved were recollected in tranquillity with gales of laughter. The result was one the most vibrant and vast collections of sound documents about British English ever assembled. And it's worth pointing out that, unlike Orton's SED, the Voices survey covered both urban and rural speech (SED was rural) and included contributions from every nation in the UK, whereas the SED reflected only the dialects of England. Again, unlike the ground-breaking work of the earlier study, Voices selected speakers from widely varied backgrounds, women just as much as men, young as much as old, and with strong participation from Britain's BAME community.

Voices was an amazing project, with over 700 hours of recordings gathered, a whole week of special programming on local radio in which the already huge bank of material was augmented daily. Radios 2, 3 and 5 all devoted time to the project and across six weeks, Radio 4 broadcast Word 4 Word, that explored all aspects of the way we speak in 21^st century Britain. Voices was a project too for the digital age, and while this was pretty much still pre-Facebook and Twitter, the possibility of making virtually unlimited, perfect-quality digital recordings rendered the gathering process simple and flexible. For Stanley Ellis, fieldworking for Harold Orton fifty years previously, recording had been on disc, in a van, or later on a portable tape-recorder with a time-limit of fifteen minutes per reel. And while the mapping of dialectal variation in the mid-twentieth century was done with isoglosses on printed maps, in Voices we were able to create a website that offered interactivity, audio-on-demand at the click of a mouse, and a vast range of possible applications and variations. It was a product for its time. Curiously, ten years on, such has been the speed of development online, the Voices website now looks clunky and dull, very much a creation of the early days of web-content.

It's with some fondness that I remember the occasion when the then Director General of the BBC, Mark Thompson, ceremonially handed over copies of all the Voices recordings to the British Library for safekeeping in perpetuity. It was a signal moment: just as no doubt, sadly, but inevitably, many of the older (and perhaps a few of the younger) Voices participants are no longer here to share their rich local speech with us, the state of English has since moved on, developed and re-configured. Voices was a systematic and rigorous mapping of the river of language across a year from 2004–2005. It was an audio snapshot, a screengrab of the state of the language, but it could, in reality, be nothing more.

Since then, we've ceased to hear about the chavs that were, seemingly daily, becoming a growing menace in British towns in 2005, and we've even stopped using station to designate where we catch the 1102 to Burnley; it's now universally, officially on signage and (heavens above) even in Radio 4 news bulletins – and tautologically in my book – train station. Since then, too, we've learned to pronounce leverage differently and to express ourselves in 140 characters. Language in all its forms flows on, unstopped and unstoppable, and while Dr Johnson and the Académie Française have at times sought to record and fix those forms and formations, it is – as every Descriptivist knows and every Prescriptivist would, sighingly, refuse to accept – an impossible task. That is the joy of language – it defines who we are, what we want to become, the social group we belong to, the part of the country we inhabit and the circles in which we move. It speaks of who we want to be too, as every UK journalist who's been tempted to write ‘I took the elevator to the 34^th floor …’ (rather than good old humdrum lift) because it sounds, well, more zippy, with the unspoken suggestion that the writer actually spends half his or her life tramping the sidewalks of Manhattan.

Speaking of which, I was myself perplexed when, in a perfectly respectable chain hotel in Manchester a year ago, the receptionist – unquestionably born and raised in the north west of England – suggested I took the elevator to reach my bedroom. Had he been told by a style-conscious management to use the Americanism? Had he found it easier to use the non-British term because of the numbers of guests visiting the hotel from across the Atlantic? Or was he simply just part of the slow-moving glacier of language-users who switch terms because, for some unfathomable reason, they simply choose to? Many of the impulses for language change are very difficult to detect, but change it certainly does. And while I found myself saddened, just slightly, by the little death in Manchester of the word lift, I knew that mourning was pointless.

Yet I shall continue to say ‘station’, even while my interlocutor looks perplexed at the use of the newly naked term – someone actually corrected me the other day: ‘you mean the train station?’, as if there were more than one. (And, before you protest that I could have meant bus station, no one says ‘station’ to mean ‘bus station’.) So, I suppose, in my little way, I'm turning just ever-so slightly prescriptivist, as I feel the flow of neologisms and new-shaped grammar beginning to leave me behind.

I guess ’twas ever thus.