Carpooling is when two or more commuters ride together in a private automobile on a continuing basis, regardless of their relationship to each other or the cost of sharing agreements. Carpooling is the simplest and most common "ridesharing" arrangement. 

Finding someone to carpool is easy because employees of a single company often live near each other. Neighbors may work at different companies located only a short distance apart and have the same work hours.

Carpools can be arranged in one of the following ways: 

• One person may drive all the time, while the passengers contribute only to the cost (e.g., gas and parking).
• Participants may alternate driving and not exchange money.
• The carpool driver may pick up passengers at their homes, or they may meet at a central location.
• Carpools can and do include family members.

You get the picture. Collectively, the carpool participants make up the rules and schedule.