What describes a guidon?

A guidon is specifically described as a swallow-tailed flag. This distinctive shape allows it to be easily recognized and serves a practical purpose in military formations and signaling. The guidon typically represents a unit and is used in various capacities, such as identifying a company or troop in a tactical setting. The swallow-tailed design is not just for aesthetics but also aids in visibility during maneuvers.

While other types of flags and banners exist, the key defining characteristic of a guidon is its swallow-tailed shape, making it stand out from other flags, such as standard rectangular flags or pennants. Additionally, ceremonial swords are not related to the description of a guidon, further supporting why the swallow-tailed flag is the correct identification.