In the High Court today, a man complained of a noise made by an amorous couple in the flat above. Each evening, they'd sing the Red Flag, then eat supper and have fun on the sofa, and take a very naughty bath together. So every night, it was hammer and sickle, cheese and pickle, slap and tickle, and bubble and squeak.

It's an archetypal Two Ronnies gag, a perfect example of the concise wordplay and twinkling innuendo that came to define the much loved, and still much missed, duo. Running for 12 series, from 1971 to 1987, Ronnie B and Ronnie C - Big Ronnie and Little Ronnie - delivered an inimitable blend of quick-fire jokes, character sketches, monologues and elaborate romps, as well as their famous musical finales (often involving outrageous cross-dressing), to an adoring public. Of the plethora of velvet-jacketed, bow-tied, shiny floor double acts from the "Golden Age of Television", they were rivalled only by Morecambe & Wise in the audience's affections. But their approach was very different.

Whilst Eric & Ernie played versions of themselves, The Two Ronnies were nearly always in character. Morecambe & Wise worked, during their halcyon period, with one writer; mercurial Liverpudlian joke-smith Eddie Braben, The Two Ronnies employed a team (combining many of the greatest comedy writers of their generation, plus, of course, the mysterious Gerald Wiley). Eric & Ernie nearly always worked together, Ronnies Corbett and Barker carefully maintained solo careers. Eric & Ernie clambered their way to the pinnacle as a double act, Barker and Corbett were constructed, already having established careers. What can be said, though, and said objectively, is that both duos created an enduring cultural legacy.

Picking a favourite, therefore, is almost impossible - indeed, for comedy aficionados, practically sacrilege. But, if I had to choose, I'd go for The Two Ronnies. The dextrous verbal wit. The bawdy pastiches. The naughty songs. And they looked so funny together. "Ronnie Barker, in a Peter Sellers-type way, can transform himself miraculously into other people," noted writer David Renwick, who began his television career on the light entertainment behemoth, before rising to greatness with his sitcom masterpiece, One Foot In The Grave. "Ronnie Corbett's own twinkly personality shines through in every role he plays."

Ronald Balfour Corbett and Ronald William George Barker first met in 1963. Corbett was 32 and making ends meet during an unwelcome 'resting' period - he had already begun to carve a niche for himself as a reliable comic performer - by working as a waiter at the Buckstone Club in London. Barker, a year older, was already established, largely thanks to his work alongside Jon Pertwee, Leslie Phillips and Stephen Murray in Lawrie Wyman's hit radio comedy The Navy Lark. The two became friends (Barker would embellish stories of their early meetings by saying that Corbett used to stand on a box when serving behind the bar) but wouldn't work together professionally until 1966, when David Frost invited both men to join his comic ensemble in The Frost Report.

In 1970, their chemistry was noted by the BBC's Head of Light Entertainment, Bill Cotton. A hitch at an award ceremony at the London Palladium had led to the two performers being called upon to provide some impromptu entertainment. Impressed by the two men's repartee - physically there was an echo of Laurel & Hardy, though their metier was language play rather than clowning - Cotton leant over to his companion, BBC 1 Controller Paul Fox: "How would you like those two on your channel?" The 'hest', as Barker might have said in one of his trademark word-mangling monologues, is 'ristory'.

At 8:15pm, on 10th April 1971, the new show hit our screens. "We decided actually to call the series The Two Arthurs," explains Ronnie C, in the opening section. "But then we thought that wouldn't work because Ronnie Barker isn't called Arthur. So we decided to call it A Ronnie And An Arthur - but then somebody pointed out that I'm not called Arthur either. So we rather smartly thought up the title The Two Ronnies."

"Thank you, Arthur," replies Ronnie B.

Overall, it's a somewhat scrappier offering than we would become used to. Even these two consummate professionals, and their massively accomplished producer/executive producer team of Terry Hughes, who would later move to Hollywood and bring to life The Golden Girls, and Britcom legend Jimmy Gilbert (Whatever Happened To The Likely Lads?, Last Of The Summer Wine, Fresh Fields) were still feeling their way. But the spirit, and structure, of each episode of The Two Ronnies remained largely unchanged for the next 16 years.

It's a simple but effective format. Start with the Ronnies behind a desk (in the first episode accompanied by some dreadful CSO, happily swiftly abandoned). A party sketch. A monologue from Ronnie B. A lavish pastiche, such as The Phantom Raspberry Blower of Old London Town. Ronnie in the Chair. A big musical set piece. Back to the desk: news items, and it's goodnight from him. It sounds easy, and they made it look easy, but, if the mere physical act of making 6 or 8 high quality hour-long shows was draining, generating the quantity of first-rate material required was a Herculean task. A task everybody involved in the production took extremely seriously.

The stars themselves were ruthless. "If either of us didn't like a joke, it was out, it was certainly out," explained Barker. "You know, if I loved a joke, and Ronnie said, 'I don't like that', it would be out - without question. You didn't have to give a reason, it was out. And that worked a treat. And the same with sketches."

Many of the writers who worked on the series enjoyed - or would go onto enjoy - significant acclaim in their own right. You'll recognise the names. John Sullivan, David Renwick, David Nobbs, Michael Palin, Terry Jones, Spike Milligan, Barry Cryer, Graham Chapman - all contributed. Other key behind-the-scenes figures, such as script editors Ian Davidson and Peter Vincent (who also wrote 7 series of Sorry! for Ronnie Corbett) or Spike Mullins - responsible for many of Corbett's masterful shaggy-dog monologues - are less well-known by the general public, but integral to the show's success. However, one writer became more associated with The Two Ronnies than any other. He, of course, is Gerald Wiley.

The production team were bamboozled. Sending a brown envelope of material into the office every Friday, but previously unknown to anyone - who could he be? The quality of his unsolicited work suggested he must be professional. A serious author, perhaps: somebody who didn't wish to be associated with a light entertainment show publicly? Tom Stoppard? Harold Pinter? After keeping up the pretence for as long as he realistically could, Barker revealed himself, with a theatrical flourish, as the Real Gerald Wiley at the Series 1 wrap party.

But if Barker's original motivation for his pseudonymous writing persona was to avoid special treatment, the revelation of his identity seemed to afford him exactly that. As the shows went on, problems began to emerge. With Barker - still credited on screen as Wiley - penning more and more, a number of other writers felt they were being overlooked. Both David Nobbs and Dick Vosburgh accused Barker of stealing their ideas. Vosburgh was particularly cross; when he saw a Wiley-credited 'pispronunciation' sketch rehashed from his own earlier contribution, he sent Barker a telegram reading, "Ronnie Parker, you're a brick". He also demanded half the money - which he got. There was a sense, as time went by, that the playing field had been unfairly tilted.

Everybody has their favourite sketch. 'Four Candles'. Renwick's own masterful Mastermind parody (which, in a state of characteristic dissatisfaction, he originally discarded, then had to pull from the bin and Sellotape back together, because his deadline had hit and he hadn't thought of anything better). The cleaning ladies, pushing their trolley into the orchestra stalls, and singing to the tune of Chinatown, My Chinatown:

Yes, The Two Ronnies was broad. But it was carefully crafted and deeply affectionate, too. The sometime naïvety is a reflection of its skill. It is gloriously accessible, and uncompromisingly warm.

By the mid 80s, however, tastes - arguably not in the country's living rooms, but certainly in the comedy industry - were changing. Alternative comedy had arrived, and its practitioners had their typewriters (if not their gunsights) readied to take down the old Establishment. Barker himself was rather antipathetic towards the young upstarts carousing through Television Centre, and made this known both in public and to the Corporation's management. The bear had been well and truly poked.

"We like birds, we're ornithologists, 'orny, porno-thologists," sang Mel Smith and Griff Rhys Jones, in Not The Nine O'Clock News's savage parody, The Two Ninnies. Written, according to its producer John Lloyd, by a disaffected Ronnies writer, the sketch cut deep. "I loved it, I thought it was hilarious, that send up," said Peter Vincent. But the stars themselves were less amused. 'The Guv'nor', as Barker had become known, was openly offended. Corbett, though content to brush it off in public, later admitted he'd found it "cruel". The truth, perhaps, is that Barker had been prepared to launch a broadside at the new kids, not anticipating the ferocity of their response. Corbett simply got caught in the crossfire.

David Renwick felt there was a nugget of truth in much of the later criticism. "A lot of the stuff wasn't as innocent as people might make out and was sexist," he explained. "And was end-of-the-pier, vaudeville, seaside postcard, yes - but actually, you know, weren't we a bit more mature than that now?" Of course, The Two Ninnies, in its parody, also highlighted why The Two Ronnies worked: it was a family show. Not The Nine O'Clock News was more avant-garde, adult, experimental fare. The Two Ronnies operated within parameters - prime-time, pre-watershed, BBC One - that allowed their jokes to seem naughty. If the shows had swapped their transmission slots, neither would have succeeded.

This applies today. Even in the 'on demand' age, we implicitly understand the rules shows are expected to operate by. If you want to recreate the outrage of a naughty joke - and notice, there is a particular kind of audience reaction you get in response to smutty material - at 7:30pm on BBC One at 10:30pm on a digital channel, you have to be much ruder. But here's the thing: neither way of doing things is inherently 'superior'. Of course, irreverent programmes like Not The Nine O'Clock News should exist - but we should have shows in the spirit of The Two Ronnies, as well. Both can be enjoyed; both are, within their contexts, appropriate. You don't have to pick a side.

It was while in Australia, following a health scare, that Barker decided it was time to call it a day, telling Corbett and producer Michael Hurll that he'd do one more series in the UK and that would be it. True to his word, Christmas 1987 marked The Two Ronnies' last show. Barker would remain largely retired for 20 years, running an antiques shop in Chipping Norton, deepest Oxfordshire, emerging only occasionally in later years for serious dramatic work. Corbett would continue performing on the stage, on television, and on radio, and in his seventh decade enjoyed a renewed lease of TV life, working with many of the comedians who had grown up watching him. And there was, in 2005, a final series with an ailing Barker, presenting, from behind their trademark desk, highlights show The Two Ronnies Sketchbook.

Ronnie Corbett, in later life, would reflect that he and Barker enjoyed "a very British friendship". "I think we were both somewhere slightly to the right of centre in our political views, both more humanist than religious in our beliefs while subscribing to, and being influenced by, the moral principles of the Christian society in which we had been brought up."

Ultimately, it was a relationship based on respect and trust. When in rehearsal, they would pick which sketches to learn that night, then be word perfect by the morning. "There was no question of one of us saying, 'I stopped at the Beehive on the way home, had a few jars, then watched the football and, bugger me, I wasn't in bed till one.' We were both totally professional."

When viewing The Two Ronnies now, it's that combination of professionalism and shared values - shared culture, even - that shines through. Of course, the show is sending Britain up, but it's sending it up affectionately, from a position of sympathy. It's 'small c' conservative; their clear regard for the world they are lampooning representing a markedly different attitude to many in our current cultural clerisy. Boundaries are pushed, but the line is never overstepped. The Establishment are twits, sex is to be sniggered at. Manners should be observed. Much of the humour plays with authority. It's naughty but never nasty - and it wears its intelligence lightly.

The Two Ronnies reflected Britain. And Britain loved them for it. We still do.