Petrol, Diesel, Hybrid, Electric.There's plenty of choice out there at the moment when it comes to selecting a power source for your new car.
There are pluses and minuses in all cases. Cost, fuel availability, range between recharges. All are factors, and so far, even after several decades of experiment and development, petrol and diesel still make more sense for everyday use to most people, although hybrids of one kind or another are making progress.
But the picture is about to change if Toyota and Honda have anything to do with it.
In fuel terms, hydrogen is the new kid on the block.
So new in fact, that we're unlikely to see any for a while yet, but in Japan and California vehicles powered by hydrogen fuel cells have been on the roads for several years. However the two Japanese companies have now taken things a stage further by rolling out a pair of saloon cars - concept cars still, but a lot closer to production reality - powered by hydrogen.
The Toyota one goes by the name of 'Mirai' which means 'future' in Japanese, while Honda have simply decided to call theirs the 'FCV' which stands, in case you were wondering, for Fuel Cell Vehicle.
So, What's a fuel cell ?
Basically it's a device which uses the chemical reaction between hydrogen and oxygen to generate electricity which is then used to power the vehicle through an electric motor. Exactly how this takes place remains a mystery to me, but it does, and the good thing is the fact that the by-product from this is good old-fashioned H2O, otherwise known as water.
Both Honda and Toyota - the latter represented by Mr Toyoda himself, stress the fact that hydrogen is easily stored and transported - more easily, in fact, than petrol or diesel, and that each if their two new cars can achieve some 300 miles of running between refills - Hondas one will, they say, go further - and that refuelling takes between 3 and 5 minutes, rather than the several hours battery electric vehicles require to bring the charge up to the mark.
There are downsides of course. There always are.
In this case there's the fact that, as of yet there are no hydrogen filling stations, or very few at any rate, and so far these are mostly to be found in Japan and California. However historians will point out that there was a time when there were no petrol stations either - petrol used to be sold by local chemists ! - but that they soon came into being once a demand was identified.
In the meantime, Honda have devised what they're calling an 'external power feeding device' which might help to make hydrogen cars more real-world-usable in the shorter term.
There's also a question of cost, both of the fuel and of the vehicles themselves.
Inevitably the first ones will be expensive I feel, but as their popularity grows, prices should come down.
Of course the jury is still 'out' on hydrogen as a power source, although both manufacturers stress that hydrogen can be made from a number of different ingredients, including garbage.
However it must be a realistic option if only because nearly all the major car makers are working on similar ideas, and have been for some years. Big names in the US and Europe have had prototypes running under test conditions for quite some time, and of all the possible alternatives to fossil fuels, the fuel cell system appears at the moment to be potentially the best one.
And it's getting closer.
According to Honda, their FCV will be ready to go on sale in 2016. Toyota on the other hand, feel that theirs is ready to go right now.
As Mr Toyoda said when the Mirai was launched last week: "This is a car which lets you have it all, with no compromises,
"The future has arrived, and it's called Mirai. We are ready to deliver."