Managing Travel Demand

Appendix D: Glossary

This glossary provides common European definitions of many terms used in this report.

Accessibility: The ability to reach something desirable (which does not necessarily involve moving cars or even people).

Car sharing: A collective form of car ownership that allows members to access and pay for car use by the hour or day. Note: in the United Kingdom, car sharing is the term for carpooling.

Charging: Pricing of travel by charging the traveler to access a congested area or cross into that area.

Collective transport: Innovative services that group travelers into shared travel arrangements, such as carpooling, taxi-sharing, and targeted public transport services.

Demand management: Reducing the demand for automobile travel during peak periods of use. In the context of this report, it means to provide travelers effective choices to improve travel reliability.

Measure: Synonymous with the U.S. use of the term "initiative," an effort such as congestion pricing, improved public transport information, etc.

Mobility: The need to move oneself or travel to access desired activities.

Mobility management: Often defined as "soft" measures to promote, coordinate, and support the use of travel alternatives that reduce the use of the automobile.

Reliability: In the context of travel time, the perceived relationship of anticipated to actual travel time for a given trip or on a given facility.

Sustainable transport: Nonmotorized transportation (e.g., walking, bicycling, public transport) that does not use nonrenewal energy sources and does not adversely affect the environment.

Traffic management: Measures that more efficiently move vehicles on the road system by offering information on or modulating the time of day, route, location, or even lane of travel.

Transportation demand management: Reducing the demand for the single-occupant car during the most congested periods of the day using measures that provide choices to travelers on mode, time of day, route, and destination of travel.

Travel planning: Development of policies, actions, and services that encourage and incentivize commuters, students, and other travelers to use alternatives to driving alone.