Some Rules And Changes Of This Year's Formula 1

The most obvious rule changes revolve around the aerodynamics. The aims have been twofold: to reduce downforce, or aerodynamic grip, and to change the balance of that grip. Last year the Overtaking Working Group came up with proposals that the FIA has adopted, working on the basis that without change a following driver needed a competitive advantage of 2.2sec in order to stand a chance of overtaking the guy in front.

The rear wings are smaller this year, and the fronts much wider.
The other key element has been to reduce the turbulence that makes a following car lose frontal downforce and understeer helplessly in a leading car's wake.

The most controversial area is the diffuser at the back of the cars which helps to generate downforce.