LINGO: Sunroof vs. Moonroof
I really didn't know the difference between a sunroof and a moonroof - I only worked it out yesterday. So I thought I'd share it with you. I had always imagined that a sunroof and a moonroof were exactly the same thing, but now know the rather significant difference.
A sunroof is essentially a large glass panel in the roof of a car, which is almost always heavily tinted (so all the UV rays don't come into the car and sizzle the top of your head). The idea is that you can see through the glass and up to the wonders of blue skies. Sometimes however, it is simply too hot or too sunny for that kind of thing, so you can usually cover the sunroof from the inside with a retractable sheet of plastic or fabric which shields you from the light. Alternatively, if you're diggin' the sunshine, you can (usually electrically) make the sunroof glass slide up over the top of your roof, and let the golden rays of sun in. Hence, this is why it is called a "sunroof."
A moonroof is very similar, except for one important missing feature. With a moonroof, you can't allow the glass panel to slide away and let the sunshine in - it's a fixed panel. I suppose that's why it's called a "moonroof" - you can't let the golden rays of moonshine in, no matter how hard you try.
All this is illustrated with this picture below. On the left of the picture is a sunroof for the front passengers - it's letting the sun in. You can also see a plastic grab handle in the middle of the roof which allows you to cover over the glass (you might need to click the picture so you can see it in a larger format). To the right of the picture is a moonroof for the rear passengers, which has all the features of the sunroof, without the ability to let the sun completely "in", if you know what I mean.
Another cool feature you might hear of is a "panoramic sunroof". I've included this picture of one in a Citroen C4. The thing that makes it "panoramic" is that unlike the sunroof and moonroof in the previous picture, a panoramic sunroof spans the entire roof length of the car. It's like one giant sunroof. Except for the fact that it really should be called a panoramic moonroof, because it's one huge big fixed glass panel, and cannot allow sunlight properly "in" - unhindered by tinted glass.
Okay, there really isn't a huge difference between these things, but if you're going to splash out such a huge amount of money on a sunroof/moonroof (usually about $2000), I think you might want to make sure it has all the features you want.
LINGO: Cruise Control
To sum up cruise control in one sentence, you would say this - it maintains a speed you've set for your car, without you having to keep your foot on the accelerator.
It may come as a surprise then, that a blind man called Ralph Teetor invented the first cruise control for cars in 1945. As my old, senile, arrogant History teacher used to tell me: "necessity is the mother of invention". For a change, he was right. Mr. Teetor was really frustrated with the way every time he rode in a car with his lawyer, the car would never seem to keep a constant speed.
So anyway, the system itself. Cruise control is most common in American cars, where long straight interstate highways are typical drives, but in European cars it is also quite readily seen, since they have lots of Autobahn-like roadways spanning the continent. In Japanese cars it used to be quite rare, since Japan lacks roads like the ones mentioned above, but Japan are increasingly producing cars for world tastes, and nowadays cruise control can be found just about anywhere. It's great if you do a fair amount of freeway driving, where you don't want to accidentally go over the speed limit and get a ticket, or tire yourself out to much on a long drive. Studies have shown that using cruise control can also lower the fuel consumption of most drivers.
So the example I've used to show you how it works is a Chrysler from the late nineties - primarily because it's designed for Americans, so it isn't too confusing for their questionably sized minds. But really, it was the easiest to explain. Cruise control systems don't look the same on every car. Some cars have buttons attached to the steering wheel, like this one, or buttons actually on the steering wheel , or a stalk protruding from the steering column, like the stalk to operate your windscreen wipers. Different brands do it different ways. But they all have similar functions, and the same basic ideas.
This example has on/off buttons, which not all cruise control systems have, since they are rather superfluous. Hitting the "on" button doesn't actually do anything, other than tell the car that you might be pressing another button soon, so those buttons are then activated. The "off" button disables the cruise control, meaning you have to once again control the speed of the car with the throttle (which is a fancy name for the accelerator, if you're wondering). But the thing is, not all cruise control cars will have this button, because touching the brakes (or the clutch too if you're in a manual) will automatically disable the cruise control. Nifty, huh? So if you're on the freeway cruising at 95, and suddenly need to slam on the brakes, you can do so without the car accelerating against you. So you can see why some cars don't have these on/off buttons, because their not really needed.
The "set/accel" button is the one that actually sets the cruise control to work. Whatever speed you're doing at the time you press this button, the cruise control will then maintain, so you can take your foot off the accelerator. So say for example you've just set your speed to 95. But now you want to accelerate to 100 - all you have to do is tap this same button five times, and it will increase your speed by five kilometres per hour. Some poorly coverted cars may still operate in miles per hour, so if you press this button five times, it will increase your speed by five miles per hour instead, which is like eight kilometres per hour, so be careful!
Holding down the "coast" button is exactly the same as what would happen to the car if you took your foot off the accelerator normally - it allows the car to roll, or "coasts". But say for example, we've had enough of cruising at 100 kmh, and wanted to get back to 95 - all we'd have to do is tap this button five times. So it works exactly the same as the "set/accel" button. Simple, right?
Except, like I said earlier, not all cars will be set up like this one - for example, there might just be a set buton, and a coast button, and then two other buttons, one with a "+" , the other with a "-". But it surely doesn't take a genius to work out what they do - it may look different, but it will have the same functions.
Oh, I almost forgot - the button that says "resume" is a handy little feature, too. If you've recently braked, and thus disengaged the cruise control, pressing this button will take you back to your last set speed. Easy.
Right, but I do have to say - you can't use cruise control at just any old speed. The minimum speed for a cruise control to activate is different, depending on the car, but usually it is somewhere between 40-60 kmh. It's so that you don't use it while you're driving in suburban streets, where the traffic is more variable than for instance, a freeway.
I don't think anyone really wants to know how it works - it's complicated... - but if one of your friends asks you about it, and you want to look smart, mumble something nerdy and throw in the term "vacuum actuator", 'cause that should do the trick nicely.
These days, as technology grows, premium brands like Mercedes-Benz have developed even better forms of cruise control - called "adaptive cruise control". It's so called because it uses a radar to adapt the speed of your car to maintain a safe distance between you and the car in front. So if the car in front of you slows down, the cruise control will automatically slow down to match them, leaving you enough space if you ever need to brake suddenly. No button tapping required. It's pretty fancy, isn't normally a feature on everyday cars, and can get rather wierd when your car comes up with a display that can measure the distance between you and the car in front while you're driving (like this Mercedes-Benz S-Class, which debuted some of this technology back in 1999). Yes, I know it's nuts.
So that's cruise control. I know that was a long explanation, but it seems that no-one is willing to thoroughly explain it - probably because they assume it's common knowledge. But I think the truth is that quite a lot of drivers who have cars with cruise control don't know how to use it effectively, or are confused by all the buttons, or simply dismiss it as a lazy way of driving. This, of course, is silly, because you've probably realised by now that cruise control has a lot of merit. At least you know all about it, now.
LINGO: Understeer and Oversteer
When a car doesn't drive exactly where you've told it to on the steering wheel, that's called either understeer or oversteer depending on what the car is doing. And I don't mean you can blame your shoddy driving on your car. Usually, when understeer or oversteer occurs, it is the driver's fault, becuase you've reached the limits of what the car's handling ability can achieve. Allow me to explain:
UNDERSTEER
We call it understeer when the car doesn't turn sharply enough into the corner. In other words, it doesn't steer as much as you want it to. This phenomenon is usually associated with front wheel drive cars (power from the engine going to only the front two wheels), but it can happen with all types of cars. The reason for understeer is the loss of traction or grip on the front two wheels, and this is more common in front wheel drive cars because the front end of the car is usually heavier. Basically, if you're understeering, it's because the car isn't capable of sustaining the current speed through a corner. So if you don't want to understeer, don't take corners too fast, basically. But sometimes understeer can occur when the road surface is very slippery, like during rain, in an oil slick, or something like that.
OVERSTEER
Oversteer then, is the complete opposite of understeer - when a car turns in too sharply into a corner. It steers more than you wanted it to. Oversteer is a trait grouped with rear wheel drive cars, because oversteer occurs when there is loss of traction or grip in the rear wheels. Starting to get it now? To some, oversteer is highly desirable, because providing it is controled (ie "countersteering" by turning the wheel in the opposite direction to balance the car), it can look cool, and result in a drift. But to average people like you or me, oversteer means that we could end up facing the wrong direction. So again, slippery surfaces can cause it, and excessive speed into a corner can cause it.
Either way, if you oversteer or understeer on the road, you're probably a bit of a danger to other road users and need to reassess the way you drive. Remember to be smooth around corners, because you shouldn't need to put your foot on either the accelerator or the brakes midway through a corner.
