Both IndyCar and F1 are open-wheeled, single-seater racing formats. This means that the cars can only fit one person and have uncovered wheels that protrude from the body of the vehicle. Despite their basic similarities, F1 and IndyCar offer very different experiences.  In F1, there are only 10 teams, with two drivers apiece for a total of 20 drivers. Most races must go for 305 kilometers, which is about 190 miles. Each driver needs to use two different types of tires in the race, so a pit stop is mandatory, though cars are not allowed to refuel. Races average around two hours in length and are held at venues all over the world.  Teams spend hundreds of millions of dollars each year developing their cars. All cars must have certain elements -- for example, gearboxes must have eight gears plus a reverse and last for six consecutive races -- but teams have leeway to tweak and change some parts of their car, including their engines, in the pursuit of speed.  In contrast, the cars featured in IndyCar are more standardized. They all have the same aerodynamic kit and chassis and can only be powered by one of two engines -- either a Honda or a Chevrolet. That said, teams are allowed to develop some of their own parts, like dampers and some of their suspensions.  IndyCar races occur on a wide range of tracks, from fast ovals to road and street courses. The length of the races also varies, with some, like the Indianapolis 500, lasting 500 miles and taking over three hours to complete. Not surprisingly, refueling during pit stops is a big part of the strategy during IndyCar races. Teams can field more than two cars, meaning that the number of drivers on the grid varies from race to race.  IndyCar is mostly considered an American sport and does not have the same level of money and glamour associated with it compared to the globe-hopping F1 circuit.