The significance of the guidon is that it represents the unit and its commander. When the commander is in, his or her guidon is displayed for everyone to see. When he leaves for the day, the guidon is taken down. It is an honor, although sometimes a dubious one, to be the guidon carrier for a unit, known as a "guidon bearer" or "guide". He or she stands in front of the unit alongside of the commander (or the commander's representative), and is the rallying point for troops to fall into formation when the order is given. In drill and ceremonies, the guidon and commander are always in front of the formation.
The guidon is a great source of pride for the unit, and several military traditions have developed around it, stemming back from ancient times. Any sort of disgrace toward the guidon is considered a dishonor of the unit as a whole, and punishment is typical. For example, should the guidon bearer drop the guidon, he must fall with it and perform punishment, often in the form of push-ups. Other units may attempt to steal the guidon to demoralize or antagonize the unit. Veteran soldiers know not to give up the guidon to anyone outside their unit, but new recruits may be tempted into relinquishing it by a superior, especially during a unit run this is known by the phrase “loss of colors”.
There is no official definition of the term "loss of colors." However, the term, in common usage, refers to the capture of a unit's colors (flags) by the enemy in battle, or the taking away of a unit's colors as a punishment or disciplinary measure. Unit colors were a great source of pride, and victories or defeats were often expressed in terms of colors being captured from or lost to the enemy. During the Civil War, many awards of the Medal of Honor were made for the capture or defense of colors. Even then however, units which lost their colors remained intact and continued to fight. Modern warfare tactics do not call for rallying points in the open,