Once upon a time all cars had circular headlights, and the engineering was simple and I expect many would fit more than one model cutting costs as well.

Now they are any shape but round. Apart from the odd Jeep or so, manufacturers have shunned round lights for random designs, the last to drop them being the German pair of VW and BMW in the 90s.

My question is is there an engineering and design reason to create headlights in a particular shape or just fashion, as I'd have thought if one shape was better they'd all use them, but there is no particular new style at all. Just anything but round.
I personally prefer round headlights and always will, but is this ever likely to return or do manufacturers have an interest in making them obsolete? I doubt anyone outside the industry would know any details but this is Funtrivia so I'm confident

My daughter has a Jeep Liberty, and that's one of it's nicest features. The "round" headlights look like eyes! Very cute. I think the 2008 or 2009 model has a different style...Big mistake!

I think the round headlights started to go when car designers wanted to go for a more streamlined look. Shaped lights meant that the bonnet, that's hood for our trans Atlantic members, could be more aerodynamic.

And you get more reflector out of the available space.

ETA: Incidentally, a number of cars are using round (or the effect of round) headlights as part of nostalgic styling. A good example is the Pontiac Solstice roadster. The headlight reflector is still not round, but they went to pains to play up the round aspect by shaping it vaguely like a diagonal cross-section of a cylinder, and also amplifying the roundness of the lamp itself. Other examples are the Chrysler 300, with a sort of oblong headlamp assembly containing two round lamps and the new Dodge Challenger and Ford Mustang, both with classic muscle styling.

The major exceptions I know about are all Japanese versions of their own models and aerodynamic or not a few firms hack off the front ends of Nissans and Toyotas etc, and graft on amazing chrome grilles and all with round lights regardless of the original design of the front.

Mitsuoka do nothing else www.mitsuoka.co.jp and if you google an image of the March Bolero (previous model) you'll see what I mean. I really believe it must be nearly all a fashion thing as the difference in performance between the original Nissan Micra and the altered versions including the Mitsuoka Viewt which has the front of an S type Jaguar, would make any measurable difference to the performance in any area. Unless of course you know different (as Esther Rantzen used to say).

As far as performance of the light is concerned, there should be no discernible difference. The annual MOT check uses a little box that checks the beam pattern of the lights to ensure they are within limits, ie spread and direction. Some cars do, I believe, still use small round reflectors behind the shaped lens.

That was what I assumed, but it was also the whole aerodynamic thing I doubted, as they have squashed cars into identical jelly moulds all designed using the one computer program, while a few rebel with efforts like the Chrysler PT Cruiser (oddly using modern lights on a 1940s body) and Nissan Cube.

I wonder what tiny percentage fuel improvement and handling they get from taking attractive designs and flattening them to look like slugs?

This just shows what is possible if anyone bothers to design them. Sadly these are built in virtually single figures, but only as no major manufacturer will risk making a mass market version.

weismann roadster

This is the same model as my car, as you can see, it has circular headlights, and is one sexy machine!

I'm not quite sure I understand the fascination for the ciruclar headlights?

Should not really matter what type of headlights a car has, as long as they work...or is it just me?

Two things really. One, until the 70s nearly all cars had them and that was what you expected cars to look like, and with a grille they all had their own recognisable faces. Two, it must be a lot easier to manufacture a simple round housing, and often many would be interchangeable so if you broke one it must have been a lot cheaper to replace.

I get all that, but it seems as though everyone that is "into" cars is forgetting one all important factor...new technologies, and a different way for the automakers to have more of an income. The world advances, and so do cars.

Not totally true. The Japanese recognised this market in the 90s and have a vast industry converting existing cars to look like they were built in the 50s. Nissan have their own plant doing so, called Autech, and most other manufacturers offer an alternative version of a few of their cars in classic version. It really is a matter of taste and only the Japanese choose to offer their customers an option.

The Nissan Figaro was so popular there are thousands in the UK, every one imported directly from Japan. People love them and all the other versions, but unless they pay thousands extra (more than most secondhand cars are worth) importing one then very few people outside the far east will be aware of their existence. Such a shame really.

I would imagine it's the same with anything that one has an interest in. It's what appeals to them. In truth, I'm not a huge car buff, but I liked the circular headlights as well. Now, THESE are nice!