The attacks of 11 September, 2001 claimed the lives of just under 3,000 people, and set in motion events that would herald the launch of the Global War on Terror.
Lives were lost, but many more were scarred as a result of the suicide attacks orchestrated by hijackers, who flew aircraft into buildings in the US.
The following is a quiz designed to see how much you recall of the harrowing events of that day:
The author is CEO of The Third Umpire Media. He had held senior management roles at Bertelsmann, National Geographic, Fox Broadcasting, Star TV and other companies. He is also an alumnus of Indian Institute of Foreign Trade.