Carpooling: Generic term for shared driving, usually for the sake of easing a daily commute. Can be informal, among friends and colleagues, or formal, set up by a company or nonprofit.
Ride-Hailing: Services, usually for-profit, that let people use smartphone apps to book and pay for car service. Examples are Uber and Lyft.
Ride-Sharing: People pooling from a common origin point, such as a residence or park-and-ride lot, to a common destination, such as an employment center. In some cases, drivers recoup the cost of the commute or receive some de minimus compensation, but the pool driver is simply a volunteer commuter whose goal is getting to the
same destination and home again, not to profit as a commercial driver.
Real-Time Ride-Sharing: Ride-sharing arranged on short-notice, usually via a mobile app and/or social networks. Advocates contend that real-time ridesharing is not motivated by profit and is intended to ease commutes.
Slugging: An informal version of carpooling with elements of hitchhiking. Passengers congregate and get picked up casually by drivers going in their direction. Typically does not rely on mobile technology.
Transportation Management Association (TMA): Nonprofit organizations that arrange local transportation services such as vanpools/carpools, shuttles and employer transit check programs. Typically funded through a combination of public grants, business contributions and rider fees.
Transportation Network Company (TNC): Technical term used in California and Arizona that refers to ride-hailing companies.