Story:Star Trek - Infinity/25th Century Ranks

Starfleet Ranks
Primary Uniform Color Division Color
 * Gray: Cadets
 * Black: Officers
 * Gold: Admirals
 * White: Professors
 * Command: Red
 * Science: Green
 * Medical: Blue
 * Engineer: Orange
 * Security: Gold

Starfleet ranks were revamped at the beginning of the 25th Century. The previous collar pips were replaced by a hexagonal outline on every officer's uniform over the right breast. The ranks are denoting by placing triangles inside the hexagonal outline, each additional triangle representing a higher rank. Enlisted officers slightly differed, they instead had a one-piece pin that was replaced every time a new rank was gained rather than adding triangles.

In addition to this, a second hexagonal outline is on the right breast of every uniform. Pins denoting senior staff were placed here so that people unfamiliar with the ship would be able to recognize department heads more quickly and easily.