What does "signal indication" refer to?

Signal indication refers to the required action that a train operator or conductor must take based on the aspect displayed by a signal. In the context of rail operations, signals communicate vital information to train crews about how to proceed, such as whether to stop, proceed at restricted speed, or continue at normal speed.

Each signal aspect—combinations of colors, shapes, and patterns—dictates specific actions required from operators to ensure safety and compliance with railway regulations. Understanding signal indications is crucial for making timely and correct operational decisions, maintaining the safety and efficiency of train movements.

The other aspects listed, such as the color of the signal light, distance between signals, and the position of the signal arm, relate to the broader context of railway signaling but do not encapsulate the overall meaning of "signal indication" as it pertains to the actions required by train personnel upon seeing a particular signal.