The Yazidis- Who Are They and Why Are They in Today's News?

BBC News: Who are the Yazidis in 60 Seconds

The Yazidis are a religious minority in Iraq. Though they have faced persecution throughout their history, currently they suffer at the hands of Da'ish and make an appearance in western media outlets.

Source: BBC News 

Roughly 40,000 Iraqis belonging to minority groups (mostly Yazidi) were forced to flee Da'ish to Mt. Sinjar in 2014. Here there is a severe lack of food and water. If the refugees leave the mountain for more resources, they risk violent death from members of Da'ish. There have been many pleas for humanitarian aid including one from a member of Iraqi parliment, Fiyan Dakheel, who tearfully pled, “We are being butchered under the banner of there is no God but God,”
The U.S. has provided humanitarian aid to those trapped on Mt. Sinjar but has no current plans for evacuation.

In October 2014 U.N. Assistant Secretary-General for Human Rights Ivan Simonovic stated during an interview that ,"Facts are indicating that [Da'ish] actions against Yazidis may amount to attempted genocide." 

According to  an article in American Aljazeera the majority of those who have not fled the area have been shot, buried alive, sold into slavery, forced to convert, imprisoned and or sexually assaulted.