Throughout The Original Series, male officers on the USS Enterprise wear a colored shirt with a delta on the left breast, dark gray pants which appeared black on camera, and black boots; female officers wear a uniform skirt, black tights and boots, although they occasionally wear the "male" uniform. The skirts' shortness is commented upon in "Trials and Tribble-ations" (DS9); Nichelle Nichols, however, did not believe that the miniskirts were unusually short or revealing: I was wearing them on the street. What's wrong with wearing them in the air? I wore 'em on airplanes. It was the era of the miniskirt. Everybody wore miniskirts.
Rank is indicated by gold solid or dotted braids on the sleeves. The shirt color indicates crew members' branch. In the pilot episodes, command personnel wear chartreuse (which tended to look gold or yellow on film), science and medical personnel wear blue, security wears red and operations wear beige, each with a matching colored collar and undershirt (TOS: "The Cage", "Where No Man Has Gone Before"). When Star Trek went into regular production, the department colors were altered: command and helm personnel wear the green/gold shirts, operations, engineering and security personnel wear red, and science and medical personnel wear blue, all with black collars and undershirts (TOS: "The Man Trap"). Certain operations and engineering personnel wore red jumpsuits with white undershirts. The frequent death of red-uniformed security officers led to the coining of the popular term redshirt.