US takes women’s 4x100 in record time
The previous world record of 41.37 seconds was set by the former East Germany (German Democratic Republic) on October 6 1985.
Jamaica was second in a national record of 41.41 seconds, the third fastest time in history.
Veronica Campbell-Brown won her seventh Olympic medal in this race, second only to Jamaica's all-time leader Merlene Ottey by two medals.
Ukraine finished third, their first Olympic medal in this discipline, while Trinidad and Tobago failed to finish after botching a baton exchange.
Allyson Felix, who ran the second leg for the Americans said it was an amazing experience.
"It's an honour to be part of this team. Who would have thought that we would have had a world record tonight? It's amazing. Our names are going down in history," she said.
Carmelita Jeter who brought the baton home in world record time said they were comfortable and decided to run their hearts out after a sad history of baton exchange failures to take the coveted gold.
"I knew that these girls were going to run their hearts out. I knew we were running fast. I was already pointing at the clock, saying 'there it is'. There was a cloud hanging over us, with people saying 'they can't do this, they're going to drop the stick' but we did it."
"I knew that if we got the stick around then all I had to do was to bring it home," Jeter added.