Definitions & Terms
The solutions that may be implemented to address your transportation
challenges may be referred to in abbreviations or terms that
you may be unfamiliar with. This section will help you understand
the difference between a "DMS" and a "HAR", for example.
511 - Simply stated, 511 is an easy-to-remember
3-digit telephone number, available nationwide, that provides
current information about travel conditions, allowing travelers
to make better choices - choice of time, choice of mode of
transportation, choice of route.
ADA - Americans
with Disabilities Act. The legislation defining the responsibilities
of and requirements for transportation providers to make
transportation accessible to individuals with disabilities. ADA also defines how
to make facilities (buildings, etc.) accessible as well.
An aerial tramway is an electric system
of aerial cables with suspended powerless passenger vehicles.
The vehicles are propelled by separate cables attached to
the vehicle suspension system and powered by engines or motors
at a central location not on board the vehicle. Only two
such transit operations exist in New
York City and at Mountain
All other aerial tramways are at ski areas or at tourist
An aerial tramway car is an unpowered passenger
cabin suspended from a system of aerial cables and propelled
by separate cables attached to the vehicle suspension system.
Engines or motors at a central location, not on board the
vehicle, power the cable system.
Architecture – see ITS Architecture
An articulated bus or articulated
trolleybus is an extra-long (54 to 60 feet) vehicle
with two connected passenger compartments. The rear body
section is connected to the main body by a joint mechanism
that allows the vehicle to bend when in operation for sharp
turns and curves and yet have a continuous interior. (Such
vehicles are normally operated in local service in the
very largest metropolitan areas on extremely heavily-patronized
AFC - Automatic Fare Collection. The controls
and equipment that automatically admit passengers on insertion
of the correct fare in an acceptable form, which may be coins,
tokens, tickets, or farecards (stored value farecards must
be inserted again on exit, at which point an additional fare
may be required).
APTS - Advanced Public Transportation Systems,
address the transportation needs of non-drivers by leveraging
services provided by Advanced Traveler Information Systems
(ATIS) and Advanced Traffic Management Systems (ATMS) to
streamline the operations of fixed-route transit, demand
response transit and other High Occupancy Vehicle (HOV) modes
(e.g. carpool and vanpool).
ARTS - Advanced Rural Transportation Systems,
support ITS technologies that can be used in rural areas,
primarily to increase safety on rural roadways.
ATC - Automatic Toll Collection (also known
as Electronic Toll Collection). The use of electronic devices
(e.g. transponder and receiver) to automate the collection
of tolls on roadways and at entrance gates.
ATIS - Advanced Traveler Information Systems,
provide timely traffic, schedule, fare, reservation, and
weather information that provides travelers the opportunities
to make informed decisions on where to go, when to go, what
transportation mode to use, which route to take, and how
much to budget.
ATMS - Advanced Traffic Management Systems,
involve the use of surveillance technologies (e.g. machine
vision devices, sensors, and closed circuit television) and
advanced communications (dynamic message signs, highway advisory
radio, and personal communication devices) to maximize throughput
Automated Gate Access is the use of electronic
devices (e.g. transponder and receiver) to automate the process
of allowing access to certain areas.
An automated guideway car is a guided passenger
car operating under a fully automated system without an onboard
crew. One type is a downtown people mover, which operates
on a loop or shuttle route within the central business district
of a city.
AVC - Automated Vehicle Classification.
Automated Vehicle Classification (AVC) is closely related
to Automated Vehicle Identification (AVI). AVC and AVI are
used in many instances at toll facilities which charge different
rates for different types of vehicles, making it necessary
to distinguish the vehicles passing through the toll facility.
AVI - Automated Vehicle Identification
is the process of determining the identity of a vehicle.
AVI typically uses a variety of electronic systems (License
Plate Reader, or a vehicle transponder) to automatically
identify a vehicle.
AVL - Automated Vehicle Location. A system
that senses, at intervals, the location of vehicles carrying
special electronic equipment that communicates a signal back
to a central control facility. AVL is typically used to manage
fleets of vehicles.
Bicycle facilities - A general term denoting
improvements and provisions made to accommodate or encourage
bicycling, including parking facilities, all bikeways and
shared roadways not specifically designated for bicycle use.
Bicycle network - A system of connected
bikeways that provide access to and from local and regional
destinations and to adjacent bicycle networks.
Bike lane - A portion of a roadway that
has been designated by striping, signing and pavement markings
for the preferential or exclusive use of bicyclists.
Bikeway - A bikeway is created when a road
has the appropriate design treatment for bicyclists, based
on motor vehicle traffic volumes and speeds. On-road bikeways
include shared roadway, shoulder bikeway, bike lane or bicycle
boulevard design treatments. Another type of bikeway design
treatment, the multi-use path, is separated from the roadway.
BRT – Bus Rapid Transit. A type of
limited-stop service developed in the 1990s that relies on
technology to help speed up the service. It combines the
quality of rail transit and the flexibility of buses. It
can operate on exclusive transitways, high-occupancy-vehicle
lanes, expressways, or ordinary streets. A BRT line combines
intelligent transportation systems technology, priority for
transit, rapid and convenient fare collection, and integration
with land use policy in order to substantially upgrade bus
A bus shelter is a structure that allows
individuals to wait at a "bus stop" out of the elements (weather).
Most bus shelters are pre-fabricated.
A bus station is a type of transit center.
A location that has very little infrastructure--such as shelters
and/or benches at a street corner where two routes intersect--would
be a transfer point.
A cable car is an electric railway with
individually controlled transit vehicles attached to a moving
cable located below the street surface and powered by engines
or motors at a central location not on board the vehicle.
A call box is a wireline or wireless telephone
station that is setup in an area to help with motorist communications.
A call box is typically used to request assistance or report
an emergency situation.
Capital Expenses are expenses related to
the purchase of equipment. Equipment means an article of
non-expendable tangible property having a useful life of
more than one year and an acquisition cost which equals the
lesser of a) the capitalization level established by the
government unit for financial statement purposes or b) $5,000.
Capital expenses do not include operating expenses that are
eligible to use capital funds.
CCTV - Closed Circuit Television. Camera/video
technology that can be used for traffic monitoring, etc.
Circulator - When limited to a small geographic
area or to short-distance trips, local service is often called
circulator, feeder, neighborhood, trolley, or shuttle service
. Such routes, which often have a lower fare than regular
local service, may operate in a loop and connect, often at
a transfer center or rail station, to major routes for travel
to more far-flung destinations. Examples are office park
circulators, historic district routes, transit mall shuttles,
rail feeder routes, and university campus loops.
Complementary paratransit service is required
by law for those disabled persons and others not able to
use fixed-route service. Generally it must operate in the
same areas and during the same hours. The fare is limited
to twice the fixed-route fare. Service may be the fixed-route
bus agency or by a completely separate agency.
Congestion is a condition where traffic
demand exceeds roadway capacity. Congestion can be recurring
(predictable) or nonrecurring (due to special circumstances).
Congestion may occur en-route to a Federal Land ,
at the entrances to a Federal Land , or within the Federal Land .
CMS - Changeable Message Sign (see also
DMS - dynamic message sign and VMS - variable message sign).
A sign (typically an electronic sign) that can change the
message it displays.
CVO - Commercial Vehicle Operations. ITS
applications for commercial vehicle operations are designed
to enhance communication between motor carriers and regulatory
agencies. Examples include electronic registration and permitting
programs, electronic exchange of inspection data between
regulating agencies for better inspection targeting, electronic
screening systems, and several applications to assist operators
with fleet operations and security.
Demand Response (also called paratransit
or dial-a-ride ) is comprised of passenger cars, vans or
small buses operating in response to calls from passengers
or their agents to the transit operator, who then dispatches
a vehicle to pick up the passengers and transport them to
their destinations. A demand response operation is characterized
by the following: (a) The vehicles do not operate over a
fixed route or on a fixed schedule except, perhaps, on a
temporary basis to satisfy a special need; and (b) typically,
the vehicle may be dispatched to pick up several passengers
at different pick-up points before taking them to their respective
destinations and may even be interrupted en route to these
destinations to pick up other passengers. The following types
of operations fall under the above definitions provided they
are not on a scheduled fixed route basis: many origins-many
destinations, many origins-one destination, one origin-many
destinations, and one origin-one destination.
DMS - Dynamic Message Sign (see also CMS - changeable
message sign and VMS - variable message sign). An electronic
sign that can be used to display a variety of messages or
A double decked bus is a high-capacity
bus having two levels of seating, one over the other, connected
by one or more stairways. Total bus height is usually 13
to 14.5 feet, and typical passenger seating capacity ranges
from 40 to 80 people. Although common in older cities of
Europe and Asia where street capacity is very limited, only
a handful of such buses are used in U.S. transit
A dual-mode trolleybus is a trolleybus
that also has an on-board power source that can be used in
emergencies or to extend the route beyond the end of the
overhead wires. Only one city (Seattle) operates such
ESS - Environmental Sensing Station. A
general term applied to technologies that measure environmental
parameters such as temperature, wind speeds, humidity, etc.
ETC - Electronic Toll Collection (also
know as AFC - Automated Fare Collection). The use of electronic
devices (e.g. transponder and receiver) to automate the collection
of tolls on roadways and at entrance gates.
Express service speeds up longer trips,
especially in major metropolitan areas during heavily-patronized
peak commuting hours, by operating long distances without
stopping. Examples include park-and-ride routes between suburban
parking lots and the central business district that operate
on freeways, and express buses on major streets that operate
local service on the outlying portions of a route until a
certain point and then operate non-stop to the central business
Ferryboat is a transit mode comprised of
vessels carrying passengers and/or vehicles over a body of
water, and that are generally steam or diesel-powered. Since
ferries vary widely in size, costs also vary dramatically.
Small water taxis might cost about $250,000, while the largest
vehicle and passenger-only ferries cost tens of millions
Fixed-route service provided on a repetitive,
fixed-schedule basis along a specific route with vehicles
stopping to pick up and deliver passengers to specific locations;
each fixed-route trip serves the same origins and destinations,
unlike demand response. Includes route deviation service,
where revenue vehicles deviate from fixed routes on a discretionary
Government Funds are funds provided by
federal, state, and/or local governments. For some purposes,
also includes directly generated taxes, tolls, fees, and
other imposed funding sources.
GPS - Global Positioning System. A space
base radio positioning, navigation, and time transfer system
developed by the Department of Defense. The system provides
highly accurate position and velocity information, and precise
time, on a continuous global basis, to an unlimited number
of properly equipped users.
Grade separation refers to separating two
items (roads, sidewalks, etc.) that cross each other by placing
them on different levels, or at different heights, to each
HAR - Highway Advisory Radio. A low power
radio system that is used to provide traveler information,
generally specific information about the condition of roadways.
HAR systems are typically limited in their transmission range
to a radius of approximately 5 miles.
HOV - High Occupancy Vehicle. Vehicles
that can carry two or more persons. Examples of high occupancy
vehicles are a bus, vanpool, and carpool.
High Occupancy Vehicle
road or traffic lane limited to buses, vanpools, carpools,
and emergency vehicles.
An intercity bus has a front door only,
separate luggage compartments, and usually restroom facilities
and high-backed seats for use in high-speed long-distance
service. (Such buses are 40 or 45 feet in length and are
used by the largest transit agencies and private companies
on express and limited-stop routes.)
Intermodal (multimodal) are those issues
or activities which involve or affect more than one mode
of transportation, including transportation connections,
choices, cooperation and coordination of various modes.
ITS - Intelligent Transportation Systems - Using
technology (electronic systems, etc.) in surface transportation
to save lives, time and money and improve the quality of
ITS Architecture – ITS projects make
use of electronics, communications, or information processing
to improve the efficiency or safety of a surface transportation
system. Because information technology is
generally most effective when systems are integrated and
interoperable, the U.S. DOT has established the National
ITS Architecture to provide a common structure for the design
of ITS projects. The
National Architecture describes what types of interfaces
could exist between ITS components and how they will exchange
information and work together to deliver ITS user service
A kiosk is a computer terminal display
typically located in a public area such as a mall, airport,
or other area, giving real-time transportation or traffic
information for the purpose of trip or route planning.
A kiss and ride facility is a part of a
park and ride facility where commuters who are passengers
in non-transit vehicles are dropped off to board a mass transportation
Lane control refers to the ability to control
the lane or lanes of a roadway. Lane control is necessary
to implement/use reversible lanes.
Light rail (streetcar, tramway, or trolley)
is lightweight passenger rail cars operating singly (or in
short, usually two-car, trains) on fixed rails in right-of-way
that is not separated from other traffic for much of the
way. Light rail vehicles are typically driven electrically
with power being drawn from an overhead electric line via
a trolley or a pantograph.
A light rail car (or streetcar, tram, or
trolley car) has motive capability, is usually driven by
electric power taken from overhead lines, and usually operates
much or all of its route on non-exclusive right-of-way. If
built before 1960 or a modern replica of such cars, it is
called a heritage trolley car (or vintage trolley car).
Limited-stop service is a hybrid between
local and express service, where the stops may be several
blocks to a mile or more apart to speed up the trip.
Local Government Funds are financial assistance
from local governments (below the state level) to help cover
the operating costs of providing transit service.
Local service, where vehicles may stop
every block or two along a route several miles long, is by
far the most common type of bus service. Trolleybuses, unless
bypass overhead wiring is available, cannot pass the trolleybus
in front of them, and thus generally operate in local service
Loop roads are
roads (roadways) that begin and end at or near the same location. Loop roads can be either one-way or two-way roads,
and are often roads that are off the main path (e.g. scenic
LPR - License Plate Reader. An electronic
system that identifies vehicles based on their license plate.
Often used in systems for Automatic Vehicle Identification
A mode is the system for carrying transit
passengers described by specific right-of-way, technology
and operational features. Transit data are generally collected
Operating Expenses are the expenses associated
with the operation of the transit agency, and classified
by function or activity and the goods and services purchased.
A park and ride facility is a parking garage
and/or lot used for parking passengers' automobiles, either
free or for a fee, while they use transit agency facilities.
Park-and-ride facilities are generally established as collector
sites for rail or bus service. Park-and-ride facilities may
also serve as collector sites for vanpools and carpools,
and as transit centers.
Passenger Fares are revenue earned from
carrying passengers in regularly scheduled and demand response
service. Passenger fares include: the base fare; zone premiums;
express service premiums; extra cost transfers; and quantity
purchase discounts applicable to the passenger's ride.
Passenger-only ferries have only passenger
decks, though they may also have space for bicycles. They
can range from small boats about 50 feet long holding about
50 people up to the 310-foot long Staten Island ferries in
New York, which can accommodate 6,000 people. Because they
don't have vehicle decks, they need not be square-ended and
may have pointed bows and side-loading. Catamaran (double
hull) and hydrofoil (where the vehicle skims the surface
of the water) styles may be used for high-speed services.
Peak Period Surcharge is an extra fee required
during peak periods (rush hours).
Public transportation (transit, mass transit,
mass transportation) is transportation by bus, rail, or other
conveyance, either publicly or privately owned, providing
to the public general or special service (but not including
school buses or charter or sightseeing service) on a regular
and continuing basis.
Regional access bikeway - The function
of regional access bikeways is to focus on accessibility
to and within the central city, regional centers and some
of the larger town centers. Bicyclist travel time to and
from activity centers is an important consideration on regional
access bikeways. Regional access bikeways generally have
higher bicyclist volumes because they serve areas of higher
population and employment density.
Regional corridor bikeway - Regional corridor
bikeways function as longer routes that provide point-to-point
connectivity between the central city, regional centers and
larger town centers. Regional corridor bikeways are generally
of longer distance than regional access bikeways and community
connector bikeways. Regional corridor bikeways generally
have higher automobile spends and volumes than community
Rehabilitation is the rebuilding of revenue
vehicles to original specifications of the manufacturer.
Rebuilding may include some new components but has less emphasis
on structural restoration than would be the case in a remanufacturing
operation, focusing on mechanical systems and vehicle interiors.
A reversible lane is a lane in which traffic
may travel in both directions, depending on specific conditions,
such as the time of day. Typically, it is meant to improve
traffic flow during rush hours by having overhead traffic
lights and lighted street signs to notify drivers which lanes
are open or closed to driving in a certain direction.
RS-D - Road Side Detection (or Roadside
Detector). Roadside Detection is a general term for any type
of ITS technology that detects vehicles and relays information
for processing. Examples of typical roadside detection include
inductive loop detectors, closed circuit television, infrared
and microwave sensors and acoustic sensors.
RWIS - Road Weather Information Systems
collect atmospheric, pavement surface, sub-surface and video
data to provide the most accurate pavement specific weather
information available. RWIS systems can be used to manage
roadways by Departments of Transportation, and to provide
information to travelers.
A suburban bus has front doors only, normally
high-backed seats, but no luggage compartments or restroom
facilities for use in longer-distance service with relatively
few stops. (Such 40 and 45-foot buses are used in the same
manner as intercity buses.)
TIS - Travelers Information Service (or
Traveler Information Systems). Generally regarded as a radio
system similar to a Highway Advisory Radio (HAR) system,
only that TIS provides more general traveler information.
TMC - Traffic (or Transportation) Management Center.
The TMC is the hub of a transportation management system,
where information about the transportation network is collected
and combined with other operational and control data to manage
the transportation network and to produce traveler information. It
is the focal point for communicating transportation-related
information to the media and the motoring public, a place
where agencies can coordinate their responses to transportation
situations and conditions. The TMC links various elements
of Intelligent Transportation Systems such as variable
message signs, closed circuit video equipment, roadside count
stations, etc., enabling decision makers to identify and
react to an incident in a timely manner based on real-time
Transfer Surcharge is an extra fee charged
for a transfer to use when boarding another transit vehicle
to continue a trip.
A transit agency (transit system) is an
entity (public or private) responsible for administering
and managing transit activities and services. Transit agencies
can directly operate transit service or contract out for
all or part of the total transit service provided. When responsibility
is with a public entity, it is a public transit agency. When
more than one mode of service is operated, it is a multimode
A transit bus typically has front and center
doors; with a rear-mounted engine; low-back seating; and
without luggage compartments or restroom facilities for use
in frequent-stop service. (By far the most common bus used
for local service, these buses can be 40 feet long, but 35-foot
and 30-foot versions are also common in smaller cities and
on lightly-patronized routes.)
A transit center is a fixed location where
passengers interchange from one route or vehicle to another
that has significant infrastructure such as a waiting room,
benches, restrooms, sales outlet, ticket or pass vending
machines, and/or other services.
A trolleybus (trolley coach, trackless trolley) is
a rubber-tired electrically powered passenger vehicle operating
on city streets drawing power from overhead lines with trolleys.
A trolley replica bus (trolley) has an
exterior (and usually an interior) designed to look like
a streetcar from the early 1900s. (These specialized buses
are generally shorter--22 to 32 feet--and are used mostly
on historic district and tourist-oriented circulator or shuttle
A van is a vehicle having a typical seating
capacity of 5 to 15 passengers and classified as a van by
vehicle manufacturers. A modified van (body-on- chassis van)
is a standard van that has undergone some structural changes,
usually made to increase its size and particularly its height.
The seating capacity of modified vans is approximately 12
to 25 passengers.
Vanpool mode is comprised of vans (and
very rarely, small buses and other vehicles) operating as
a ridesharing arrangement, providing transportation to a
group of individuals traveling directly between their homes
and a regular destination within the same geographical area.
The vehicles have a minimum seating capacity of seven persons,
including the driver. It is considered mass transit service
if it is operated by a public entity or is one in which a
public entity owns, purchases, or leases the vehicle(s).
Vanpool(s) must also be in compliance with mass transit rules
including Americans with Disabilities Act (ADA) provisions,
and be open to the public and that availability must be made
known. Other forms of public participation to encourage ridesharing
arrangements such as the provision of parking spaces, use
of high occupancy vehicle (HOV) lanes, coordination or clearing
house service, do not qualify as public vanpools.
Vanpool service is operated in two ways.
Either transit agency vehicles are leased to companies or
directly to volunteer drivers, or the service is contracted
to a vanpool management company that has its own vehicles
and administers the service. Under either arrangement, many
vanpools serve large private corporations or government agencies
and consist solely of their employees.
Vehicle ferries have at least one deck
for vehicles, with additional decks for passengers. The largest
are in the Seattle, WA area,
and are over 460 feet long, accommodating 2,500 passengers
and 218 vehicles. Such ferries are normally square-ended
to allow vehicle access and egress.
VMS - Variable Message Sign (also known
as a Changeable Message Sign or Dynamic Message Sign). Electronic
signs which can change the message they display.
Water taxis are very small passenger-only
ferries (about 50 feet or less) that may operate in both
fixed-route and on-demand service, depending on the time
of day and patronage levels. They can load and unload very
quickly and operate very frequently, sometimes to several
different points around a harbor or along a river.
WIM - Weigh-In-Motion. A technology for
determining the weight of a commercial vehicle without requiring
it to stop on a scale.
Zone or Distance Surcharge is an extra
fee charged for crossing a predetermined boundary.