While New York which was the victim of this attack holds a ceremony where the twin towers stood, people world over are paying tribute to those killed in the attack.
The planes that turned the two symbols of American power and supremacy into rubble left a huge psychological impact which people are still trying to recover from.
The incident also had political repercussions. The debate over the US military commitment in Afghanistan grew and Americans woke up to the existence of Iraq, Taliban and al-Qaeda.
While the present US President, Barack Obama still continues to try and heal what happened, the fear of terrorism still haunts the world.