For U.S. service members and veterans, there is no more haunting or moving musical strain than the 24 notes of “Taps.”

Ever wonder why these few notes are so much a part of military life?

While the British have had a similar bugle call, “Last Post”, for more than 100 years, “Taps” is an all-American tradition dating back to the Civil War.

While its exact origin is blurred by time and controversy, “Taps” is widely believed to be a revision of “extinguish lights”, an Army bugle call that signaled the end of the day.

BG Daniel Butterfield, a former first sergeant, Medal of Honor recipient and future major general who would serve as chief of staff of the Army of the Potomac, is believed to have penned “Taps” with the help of his unit’s bugler while commanding a brigade at Harrison’s Landing, Va, during the Peninsula Campaign of 1862.

Butterfield’s revision proved so popular that “Taps” soon was adopted by other units, some of them Confederate.