Armstrong died following complications resulting from cardiovascular procedures, a statement Saturday from his family said. It didn't say where he died.
Armstrong commanded the Apollo 11 spacecraft that landed on the moon July 20, 1969, capping the most daring of the 20th century's scientific expeditions. His first words after setting foot on the surface are etched in history books and the memories of those who heard them in a live broadcast.
"That's one small step for (a) man, one giant leap for mankind," Armstrong said.
In those first few moments on the moon, during the climax of heated space race with the then-Soviet Union, Armstrong stopped in what he called "a tender moment" and left a patch commemorateastronauts and Soviet cosmonauts who had died in action.
"It was special and memorable but it was only instantaneous because there was work to do," Armstrong told an Australian television interviewer this year.
Armstrong andspent nearly three hours walking on the lunar surface, collecting samples, conducting experiments and taking photographs.
"The sights were simply magnificent, beyond any visual experience that I had ever been exposed to," Armstrong once said.
The moonwalk marked America's victory in the Cold War space race that began Oct. 4, 1957, with the launch of the Soviet Union's Sputnik 1, a 184-pound satellite that sent shock waves around the world.
Although he had been a Navy fighter pilot, a test pilot for's forerunner and an astronaut, Armstrong never allowed himself to be caught up in the celebrity and glamor of the space program.
"I am, and ever will be, a white socks, pocket protector, nerdy engineer," he said in February 2000 in one of his rare public appearances. "And I take a substantial amount of pride in the accomplishments of my profession."