You might not notice air resistance much when walking around, but in a fast-moving car, driving is like swimming through the atmosphere. Much like a swimmer, cars need to be streamlined and tested to move through the air without problems.
In more scientific terms, aerodynamic quality is measured by the coefficient of drag, calculated by shape and surface area. An average car scores a drag coefficient of 0.35, but these wonders go above and beyond.
Image by Design Milk - http://bit.ly/2mEQu8x
Some cars can't pull off "aerodynamic" without looking like a smooth blob, but the i8 plug-in hybrid manages to look awesome and aerodynamic at the same time. In addition, its drag coefficient is just 0.26.
Tesla Model S
Some of us thought all-electric cars would never make it, but we were wrong! It makes sense that a car on the cutting edge of technology would have the advanced aerodynamics to fit. The Model S has a drag coefficient of 0.24.
This supercar doesn't just look modern- it looks like it came straight from the future. While it does guzzle gas like a monster, the mileage per gallon isn't hindered by drag. In fact, it has a drag coefficient of just 0.19.