Filling the extra seats in your car means there are fewer drivers, and thus fewer cars crowding onto the roadway. The more people who carpool, the smoother the ride into work.

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You leave your driveway in the best of moods, happily ready to face a new day. But something you hear causes you to shudder and cringe -- the ominous traffic report. In a few moments, you're transformed into a white-knuckled, foul-mouthed driver, stressing about making your big meeting on time.

People in big cities expect traffic jams and must plan their schedules around these annoying delays. A 30-mile (48-kilometer) commute can regularly take more than an hour in bad traffic.

As the traffic congestion in a city worsens, people begin to look at different options to decrease their commute time. The option we'll discuss in this article is carpooling.

Carpooling, which falls under the ridesharing umbrella and is closely related to vanpooling, is simply when a group of people decide to ride together. They usually share the cost of the trip and take turns driving. Often, carpools are formed by commuters who want to avoid driving during rush hour. In a small way, these commuters help to alleviate that traffic. Carpools are also formed by parents who want to divide the task of driving children to and from school and extracurricular activities.

Now that we know why people form carpools, let's find out how they should go about creating them.