What will be the impact on oil flows of the US blockade of the Strait of Hormuz?

FILE - Oil tankers and cargo ships line up in the Strait of Hormuz 

The US military began blocking shipping traffic in and out of Iran's ports, ​a move that would prevent roughly two million barrels of Iranian oil a day from entering the world's markets, further ‌tightening global supply.

Here are details on the blockade and its implications for oil markets.