Which rank is represented by a single gold bar?

The rank represented by a single gold bar is Ensign. In the United States Navy and Marine Corps, the Ensign is the lowest officer rank, designated as O-1 in the military ranking system. The gold bar symbolizing this rank is easily recognizable and is an important part of the officer's insignia.

An Ensign typically serves as a junior officer, often taking on various responsibilities in leadership, administration, and operational roles within a unit. As they gain experience and demonstrate leadership capabilities, they can be promoted to higher ranks, each having distinct insignia to reflect their increased responsibilities.

Understanding the rank structure is crucial for recognizing the hierarchy within the military, and the single gold bar stands as an important symbol of a new officer’s entry into their professional military career.