Epaulettes are the fancy, fringed ornaments seen on the shoulders of military officers in full dress uniform, and on regular uniforms of some services, like those of the French foreign legion.
Epaulettes are a French invention, coming from the French word epaule for "shoulder." In the days before binoculars and "fatigue" style uniforms, soldiers needed to be able to identify their officers in the heat of battle. Epaulettes with their fringe are noticeable from a distance and helped identify officers. Conventions on whether to wear the epaulettes on the right shoulder, left shoulder, or on both shoulders, have changed over the years, and the French decided epaulettes should be worn on both shoulders by officers.
In the United States, military officers followed the French style of epaulettes as late as the Civil War. After that time, however, they became less popular. The British found that epaulettes, impressive-looking as they are, can be seen by snipers as well as the average soldier or sailor. When it became obvious that snipers were picking off the officers because their epaulettes made them more visible, the British armed forces removed them from the uniform. The United States military probably removed them for the same reason. Epaulettes are still seen occasionally on the most formal dress uniforms.
Epaulettes have also been used as fashion statements for women's gowns. It has often been common for women's dress to mirror uniforms when their countries are at war. Touches such as gold braid and brass buttons on garments reinforce this look, and women have worn epaulettes on formal gowns to give their fashions a military air. Designers sometimes still incorporate this most recognizable insignia into their couture.
Over the past 200 years or so, epaulettes have come to signify flashy military authority in the United States, and someone lampooning an officer will often wear outsized epaulettes for comic effect. However, epaulettes, as odd as they may seem now, once did serve an important purpose for the men who wore them, and for the men under their authority.