What is the green card lottery that Trump wants to end post NY attack?

Trump said the attacker, who ploughed a pickup truck down a crowded bike path near the World Trade Centre killing eight people and injuring 11 others, was allowed to enter the US through the programme

In the wake of the deadliest terrorist attack in the country since 9/11, US President Donald Trump on Wednesday vowed that he will terminate the popular green card lottery after an ISIS-inspired Uzbek man who entered the US under the programme killed eight people in New York.

Trump said the attacker Sayfullo Habibullaevic Saipov, who ploughed a pickup truck down a crowded bike path near the World Trade Centre killing eight people and injuring 11 others in an ISIS-inspired plot, was allowed to enter the US on a State Department programme known as the "Diversity Lottery Programme".

The annual Diversity