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.

A carpool going to work
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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.

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.

The Different Flavors of Traffic Jam
People who live in metropolitan centers are familiar with all the ways traffic jams can manifest. The patience of even the calmest of drivers is tested in bumper-to-bumper traffic: when you drive a few feet, halt, drive a few more feet, halt … you get the idea. Or what about coasting at an extremely low speed, riding the brake for miles (the fun only gets better if your car is manual). The stickiest traffic jam of all is the dreaded gridlock, defined as "a traffic jam in which no vehicular movement is possible, especially one caused by the blockage of key intersections within a grid of streets" [source: The American Heritage Dictionary of the English Language].