2016 Toyota Prius revealed

The fourth generation of the world's biggest selling hybrid has just broken cover. But having seen it, should the covers go back on?

It might look like a space ship on wheels but this is the next generation of the Toyota Prius, the world's biggest selling hybrid car.

More than 3.5 million Prius hybrids have been sold -- including 20,000 in Australia -- since an otherwise anonymous looking sedan was launched as an experimental vehicle in 1997.

The Prius has become daring with each new model but this is the most radical yet.

The futuristic styling is intended to polarise -- Toyota reckons it resembles "an athletic shape inspired by a runner in the starting blocks" --  but it's also designed to help it slip through the air like a tear drop.

While the appearance may not be everybody's idea of cool, tech geeks will likely continue to love it.

The new Prius will be available with a raft of electronic safety aids including a pre-crash system (which primes the brakes, the seatbelts and the airbags if you're about to crash), lane departure warning, automatic high beam deactivation (sensors detect oncoming cars at night) and radar cruise control that keeps a safe distance with the car in front.

There is much more to the new Prius than a green image

Unofficially, Toyota is said to be increasing the petrol-free driving distance of the plug-in hybrid version of the Prius from 20km to 40km before switching to petrol power. However that model will not be available for another year or more.

Toyota is also keeping some of the technology of the new Prius under wraps until next week's Frankfurt Motor Show.

The new Toyota Prius is due on sale in Australia early next year. Pricing is yet to be announced but the current model starts from $34,490 plus on-road costs.

As is the case with all new cars these days, the company's PR department supplies a quote about the car which doesn't really say much.

These comments are attributed to the Prius chief engineer Kouji Toyoshima:

"There is much more to the new Prius than a green image. From the bold design to the quality interior, the Prius has never had such a powerful presence".

And: "We have developed an even-better Prius by expanding its environmentally sensitive DNA while ramping up its desirability with an emotional design and an engaging drive. It offers a new perspective of what a hybrid can be."

Translated: "this is the new model".

10 things you need to know about the new Toyota Prius

1. The name Prius is Latin for "front runner" or "before".

2. The badge of the front of the fourth generation Prius is the same height as it is on the Toyota 86 sports-car.

3. Toyota has lowered the overall height of the new Prius. This gives it a lower centre of gravity and should make it feel like its hugs corners better.

4. Toyota claims to have improved the energy efficiency of the Prius petrol engine by 40 per cent.

5. More than 3.5 million Toyota Prius cars have been sold worldwide since 1997 and 20,000 in Australia since 2001. These figures do not include the baby Prius C or the bigger Prius V seven-seater.

6. The Prius was never intended to be a hit; it was originally designed to be an experimental vehicle. But Americans fell in love with it and the Prius went mainstream. That's why Toyota has been so daring with the design ever since: it's still an experiment for its vision of the future.

7. The Prius still has a petrol engine under the bonnet, but an electric motor gives it a boost from rest or when moving silently in stop-start traffic. A regular Prius can drive up to 2km in ideal conditions (a smooth flat road) at up to 40km/h before the petrol engine kicks in.

8. The Honda Insight hybrid actually beat the Toyota Prius to market but its hybrid system was not as strong as Toyota's and could not move the car from rest, so the fuel efficiency gains were modest. Honda has sold a fraction of the hybrid cars as Toyota.

9. Toyota is sharing its future hybrid technology with German car maker BMW; the two brands are working on a sports-car together and, in return, sharing the hybrid tech is part of the deal.

10. Toyota is making a splash with the new Prius in Frankfurt, rather than at a motor show in the US, the biggest market for the Prius, because Toyota is yet to conquer Europe, which has been slow to adopt hybrid technology.