1. gear
   clutch
2. toroidal ratio

Broadly speaking, the term "gear" refers to the ratio of the engine's shaft speed to the driveshaft speed. Conventional automatic transmissions change this ratio with a set of interlocking wheels.

1. a reverse gear
   a stick shift
2. a gearbox

Instead of a gearbox with a set number of gears and interlocking toothed wheels, CVTs usually operate on a pulley system that allows an infinite variability between gears.

1. the clutch
   a high-power belt
2. an output "driven" pulley

Although CVTs have various other parts, the three main components are the belt, a variable-input "driving" pulley and an output "driven" pulley.

1. high gear
   low gear
2. pitch radius

When the pulleys are far apart, the belt rides lower and the pitch radius decreases. Likewise, when the pulleys are close together, the pitch radius increases.

1. driving pulley
   driven pulley
2. variable pulley

As an output pulley, the driven pulley transfers energy to the driveshaft. The second pulley is called the "driven pulley" because the first pulley is turning it.

1. wheels
   discs and power rollers
2. variable displacement pumps

Although a system using discs and power rollers seems drastically different, all of the components are analogous to a belt-and-pulley system and lead to the same results -- a continuously variable transmission.

1. improved fuel efficiency
   a smoother ride
2. greater horsepower

Because of their construction, CVTs improve fuel efficiency, achieve better acceleration and make for a smoother ride.

1. 10 percent
   25 percent
2. 40 percent

Because CVTs cycle steadily into the appropriate gear ratio, they can reach 60 mph (97 kph) 25 percent faster than a car with manual transmission.

1. Rudolf Diesel
   Henry Ford
2. Leonardo da Vinci

In 1490, more than 500 years ago, Leonardo da Vinci conceptualized the very first CVT.

1. 1920
   1945
2. 1958

Daf (of the Netherlands) produced a CVT in a car for the first time in 1958.