The Guardian posts a 3-minute Video Guide to four years in Syria’s conflict. There are points that can be debated, such as the portrayal of the rebels, but this is a valuable introduction. And this is undeniable:

More than 200,000 people — combatants on all sides and civilians — have died.

Whole cities have been reduced to rubble, and almost half the population — perhaps 10 million people — have been uprooted in the biggest refugee crisis since World War II.