The dreaded Ebola virus has so far killed over 3,400 people in Liberia.
MH17 was a passenger flight from Amsterdam to Kuala Lumpur that crashed after being shot down, killing all 298 people on board.
Aleppo is a destroyed city with no heat and electricity. People have little food and water.
Five-year old Fatou has lost her mother and father in Ebola. She now lives together with 46 orphans outside Monrovia, Liberia.
On 22 July 2011, Anders Behring Breivik killed 69 people on the small island of Utøya, 40 kilometers northwest of Oslo, in Norway.
Honduras is the country with the highest number of murders per capita. Each year more than 7,000 people are murdered.