Box Car: An enclosed car that is used for general service and especially for goods that must be protected from the weather

Car Capacity: The normal load in pounds, cubic feet, or gallons that a car is designed to carry

Car Initial and Number: An identification comprised of initials, which indicate the ownership of the car, and a number, which specifies the type of car

Commodity: A good being shipped

Coupler: A device located at both ends of all rail cars in a standard location to provide a means for connecting one car to another

FAK: A shipment that contains multiple types of goods or "Freight of All Kinds"

Geometry Car: An automated track inspection vehicle with electro-mechanical sensors used to detect and record track geometry over long distances

Jib: A crane or derrick, also known as a boom

Blue Flag: A clearly distinguishable flag, that when displayed, indicates that workers are on, under or between equipment

Limited speed: A speed not exceeding 45 miles per hour

Carload: The amount of freight that equals a car's weight or space capacity

Classification Yard: The location where cars are organized by carrier according to their destinations, and are made ready for train movement or delivery

Flat Car: An open car without sides, ends or a top, used principally for hauling lumber, stone, and heavy machinery

Gondola Car: A car without a top that has straight sides and ends, that is used to carry freight in bulk

Line Capacity: The maximum number of trains that can operate safely and reliably over a given segment of track during a given period of time

Long Ton: A unit of weight equal to 2,240 pounds, also known as a gross ton

Serving yard: The location where cars are delivered to or received from customers

Siding: An auxiliary (or secondary) track for meeting or passing trains

Unit Train: A train operating generally intact between point of origin and final destination, normally hauling a single bulk commodity, composed of like cars, equipped with high-tensile couplers

Blocking and Bracing: Using wood or metal supports to keep shipments in place, in or on cars, or trailers