After parking, several family members recently climbed out of a big sport utility vehicle for a trip to the commissary. They had taken no more than 10 steps toward the front door when the Fort Knox mechanized bugler sounded off, alerting everyone about the pending end to the duty day.

At the insistence of the older man, all the family members stopped and stood at attention, waiting for the bugle to end. While they stood there, other shoppers continued to walk around.

"People have no respect for the flag anymore," muttered the older woman.

A shopper in a military uniform started to pass by them but stopped, instead, and suggested that they keep walking.

"That's the Assembly call -- the five-minute warning, if you will," he said. "We don't stop and render honors until Retreat plays."

Visitors to Fort Knox quickly learn that the installation plays several bugle calls throughout any given work day -- 19, in fact.

Each duty day begins with First Call, signaling it's time to prepare to assemble for a formation. Sounding off at 6:20 a.m., it effectively alerts personnel that Reveille will play in 10 minutes.

Considered one of two of the most important calls each day, Reveille signals the raising of the National Colors on the installation. The other is To the Color -- signifying the lowering of the flag at the end of the day. Both require people who are outside to stop what they are doing and render honors -- including those driving around post.

Sergeant Eric Stroupe, bugler for 100th Army Band at Fort Knox, said this is impressed with how serious Fort Knox garrison leaders take this; there are signs posted informing drivers to stop their vehicles, get out and render honors.

"We do those calls to recognize those who aren't here now, and to also instill that pride and comradery that we learn to love in the military," said Stroupe.

Bugle calls have a significant history that reaches back long before the Continental Army used them during the nation's war against England in the 18th century. Stroupe said they were used simply as a form of communication.

"It's to deliver a message to folks, to mass groups of people, without straining yourself," said Stroupe. "They didn't have megaphones back then so they went with the bugler."

There are several different calls that are still in use today. Among those that are rarely used or no longer in use due to the changing times are First Sergeant's Call, Mail Call, Church Call, Fire Call, Pay Day March and School Call.

Another significant change to the bugle calls came to Fort Knox in 1941, when leaders did away with an actual bugler and went with what they called the "iron bugler" -- essentially a record player with a microphone placed next to the speaker and piped to loudspeakers across the post. The Iron Bugler public address system went into effect in June of that year.

Unlike many other installations around the Army, Fort Knox continues to use several other bugle calls in the Army band repertoires. These include First Call, Assembly, Mess Call and Drill Call.

Arguably the most notable of these is taps. While most people attribute the call with honoring those warriors that have died on the battlefield, its original intent, according to the U.S. Army Band, was to signal Soldiers to extinguish all unauthorized lights and go to bed.

Stroupe said this call is the most important one for him to not only play, but to play correctly.

"That's the biggest one where you see definitely the most emotion, and the most pride," said Stroupe. "I've done a number of funerals, both with MEDDAC here, and on my own, and when you play it, if you don't get choked up while playing it, you know that you're doing it to honor someone in a very personal manner and the best way you can.

"As a bugler, I don't want to mess that up for them," he continued.

Stroupe said he channels the loss of his uncle, Verbon Robbins, when playing taps at funerals. Robbins served in the Navy.

"I play it to my uncle as a memorial, so I'm not only playing it to the person who I'm attending the funeral for, but also in recognition of him."

Stroupe said many buglers live by certain mantras when they play taps. One of those is "All gave some. Some gave all." Another, and his personal favorite, is "Sound the honor. Honor the sound."

"Taps is regarded as one of the more pivotal calls that we learn to play," said Stroupe. "It's the highest honor we can bestow to those that have fallen."