A cue, or signal, is a stimulus that prompts a specific response or behavior. Cues can be visual, auditory, or tactile, and they help individuals recognize when to act or react. For example, a green traffic light serves as a cue for drivers to proceed, while a bell ringing can signal students to change classes. In psychology, cues are often studied in the context of learning and memory. They can trigger recall of information or influence behavior through conditioning. For instance, the sound of a whistle might cue a dog to perform a trick, demonstrating how cues can shape responses through association.