The Monocoque

Let's start with the parts of the car. The body or monocoque (pronounced mono-cock) is made from carbon-fibre. Carbon-fibre starts out as a woven fabric, made of thin strands of carbon thread. This thread is extremely strong; you can't break even a single thread with your hands!
This fabric is placed over molds in varying layers called piles. By changing the direction of the piles and the density of the weave, different strength characteristics can be achieved. The fabric is then coated in epoxy (fancy glue) and then baked in an oven. The end result is a structure that is very very stiff and very very strong. Not only that, its also very very light.

In fact, the monocoque is so strong that it helped Robert Kubica survive a huge crash at the Canadian GP this year. He hit the wall head-on at 143 mph and experienced 75 g's of deceleration. Yet he drove himself home from the hospital...

Carbon-fibre is a wonder material, so its no surprise that most of the other parts of the F1 car are also made out of carbon-fibre, including the wings and suspension components. The end result is a car that weights 1334 lbs including driver. Compare that to NASCAR's minimum weight of 3400 lbs!

The actual cars are built much lighter than the 1334 minimum weight and then lead ballast is added to make weight. The ballast is added as low as possible in the car to keep the center of gravity as low as possible. Also, since the minimum weight includes the driver, lighter drivers do not have any advantage as they do in IRL.

Finally, check out the fantastic technical graphic courtesy of Allianz about the monocoque of their Williams Toyota.