The tense race pits incumbent President Goodluck Jonathan against former military ruler Muhammadu Buhari with an electorate divided along a complex mix of ethnic, regional and in some cases religious lines.
There are only eight psychiatric hospitals to serve more than 190 million citizens in Nigeria. To close the gap, nonprofits throughout the country are finding new ways to reach out to people in desperate need of care, from online Twitter therapy sessions to community outreach via motorized trikes.
With world leaders about to gather in New York for a UN Climate Action Summit next week, millions of young people from Australia to Iceland took off from school or work on Friday to demand urgent measures to stop environmental catastrophe.
The World has given some thought to the musical trends that have stood out over the past decade. From K-pop to viral videos to a resurgence in vinyl, host Marco Werman highlights some of these trends, and more.