The force exerted by air on anybody moving through it is called Aerodynamic Drag. The drag coefficient of an automobile impact the way the automobile passes through the surrounding air. Drag is always kept to a minimum because it has a negative effect on performance as well as efficiency because lower the drag lower is the resistance offered by the vehicle as frontal remains constant for a vehicle. The upright design of Indian buses gives it a large frontal area and drag coefficient of 1.30 whereas a raindrop has the least amount of drag. Now – a – days cars generally, have low frontal area consequently, a drag coefficient ranging between 0.4 and a low of 0.26. To reduce the frontal area the only way is to reduce the size of your car, quite impossible (except for some modification) whereas reduction in drag is possible which would help decrease the resistance. The reduction in drag in road vehicles can help in increasing the top speed of a vehicle and thereby its fuel efficiency, as well as many other performance characteristics, such as handling and acceleration. The two factors that have the main impact on drag are the vehicle’s frontal area and the drag coefficient. Firstly, the drag coefficient can be lowered which can be achieved by streamlining the exterior body of the vehicle. The streamlined bodies even have low frontal area. Streamlining the body requires characteristic use of the vehicle and assumptions over the surrounding airspeed. For reducing the frontal area – Radio antenna, Roof rack, rear spoiler, Side mirrors, Mud flaps and Windshield wipers are used whereas for fabrication Wheel covers, Fender skirts, Partial grille block, modified front bumper and Boat – tails, Kammbacks and under tray are used.