FEW cars can claim to have changed motoring history - the Ford Model T was one and so was the Volkswagen Beetle.
In that kind of company, the Mazda6 wouldn't immediately come to mind as a motoring milestone, but in its own way this car is just as significant.
For without it, Mazda Cars itself could easily have become motoring history.
A few years ago, the company was struggling. Its cars - the MX-5 two-seater apart - were unattractive, dated and selling badly. The company was under-performing in global markets and when the Asian economic crisis of the 90s hit, Mazda was close to the brink of extinction.
Ford stepped in to save the ailing Japanese maker, but even with the global giant's financial clout, it was clear that Mazda could not survive without a completely new model range.
Enter the Mazda6, the car which was to lead an astonishing revival in the company's fortunes.
Few cars can have had such an immediate and significant impact. Privately, Mazda bosses admit that without it, the brand may not have survived and say that this model alone has "propelled Mazda to levels of success that many observers previously thought impossible."
Since it arrived in 2002, the Mazda6 has been the cornerstone of a product-led revival which has seen Mazda sales across Europe surge by an astonishing 62.5 per cent.
But even with more than quarter of a million sold in Europe in the space of three years, Mazda cannot afford to rest on its laurels so this month sees the launch of a revised range of hatchback, saloon and estate models.
The changes are far from obvious - on the outside, in fact, they're minimal and owners of the original will be relieved that Mazda has not made radical changes to the design other than tarting up the grille, bumpers and head and tail lights.
It's a different story inside and under the skin, however. Mazda says the latest 6 has been improved in 30 areas with 785 engineering changes - most of them not visible.
Those you can see include smart new interior features like a high-gloss, black centre panel housing the audio system and air con controls, chrome instrument surrounds, redesigned door trims and higher quality trim materials.
In sum these changes make the cabin both more distinctive and welcoming - an all-round better place from which to enjoy the real benefits provided by the numerous below-the-surface improvements.
Most noticeable of these is the lack of noise. Mazda has made the bodyshell stiffer and added extra noise insulation materials with truly remarkable results.
This has to be one of the quietest cars in its class. Road noise was non-existent on all but the very worst surfaces encountered at the car's launch, wind noise similarly well-suppressed and engine noise only intrusive when the latest version of Mazda's 145bhp two-litre petrol engine was stretched right to the limit.
This engine - like the others in the range - has been upgraded to Euro IV compliance and now comes with a variable intake system and sequential valve timing.
Performance is adequate if not inspiring with a 131mph top speed and acceleration from 0-62mph in 9.7 seconds, but the latter disguises the fact that with its new six-speed gearbox, this two-litre petrol version is nippier in mid-range and, according to official figures, capable of returning a respectable 36.2mpg in mixed driving.
With all the latest engines boasting lower CO2 levels, company car drivers can make small savings on their tax bills no matter which they choose.
The biggest savings come on the more powerful of the two diesel engines on offer. This latest 141bhp unit is more economical than before - 47.1mpg average - and emits less CO2. With high torque at low revs and low noise levels, it's a humdinger of a drive too, accelerating effortlessly in mid-range and covering the benchmark 0-62mph sprint in 9.5 seconds.
In all 27 versions of the 6 will be available with a choice of 1.8, two-litre and 2.3-litre petrol plus the two-litre diesel with outputs of either 119 or 141bhp.
All share improvements to the suspension system with revised settings achieving the seemingly impossible trick of providing more composure and sharper handling in fast corners without in any way compromising the exceptional ride qualities of the original.
If anything, in fact, this latest model seems to soak up the bumps even better than before.
Four trim levels are on offer - S, TS, TS2 and Sport - all better specified than before ... some justification, perhaps, for a £200 price hike across the range.
All have air con, a suite of six airbags, ABS with EBD, remote central locking, alarm, alloys, height and reach adjustable steering column, height adjustable driver's seat, CD player, electric windows, powered and heated door mirrors and an outside temperature gauge.
Prices start at £14,100 for the 1.8S five door and rise to £19,200. Auto transmission is available on two-litre petrol models for £1,000 extra.
Automatic and diesel models are not expected in the showrooms until the autumn, but when the full range is available, Mazda UK should have no problems in achieving its target of selling 15,600 Mazda6's this year.
In fact, given the quality and driveability of this car, that target - only 200 up on last year - would seem to be pessimistic in the extreme.