A pantograph is the articulated device that connects the electric-powered locomotive to the overhead power supply.

A passenger car (known as a coach or carriage in the UK) is a piece of rolling stock that is designed to carry passengers.

A system that provides information to passengers regarding train operations. Information can be provided by media such as recorded voice, visual display, internet site or SMS.

Information would typically include next train to arrive data (time, platform, stopping patterns, etc); train delays or cancellations; special instructions (not taking passengers, cars out of service); and many more.

A unit of competence is described by many elements of competency.

Each element of competency has many performance criteria.

The performace criteria describe what a person should be able to do to achieve the element of competency.

A permissive signal is signal that a driver can pass when at danger (stop) provided certain rules are followed (usually stop, wait a period of time and proceed cautiously until the next controlled signal).

This is different to the limited actions for an absolute signal.

Personal protective equipment (PPE) refers to HI-Viz vests, protective clothing, hats, helmets, sun glasses, goggles, safety boots, long sleeve shirts, or other garment designed to protect the wearer's body from injury by blunt impacts, electrical hazards, heat, chemicals, and infection, for job-related occupational safety and health purposes.

During various rail constructions, it is often necessary to construct a temporary section of railway track (temporary way) to be used whilst the permanent way (perway) is established.

When facing the capital city, platforms are usually (but not always) numbered from left to right.

A panel multiprocessor (PMux) is a microprocessor that interfaces between the control panel and the interlocking. Typically the PMux converts the operator's pressing of a button (or rotation of a switch) into a electronic signal to be sent to the interlocking. In return, the PMux converts the electronic signal from an interlocking into a voltage to drive indication LEDs on the control panel.

The PMux often has non-vital logic processing to simplify the demands on the interlocking. For example, the PMux can monitor the state of the interlocking and only forward commands when the interlocking is able to process them.

A position switch is an electrical switch that is operated by a mechanical means. Position switches are made (electrically connected) when the mechanical mechanism is in one position and are open (not electrically connected) when in another position.