Zimbabwe's President Robert Mugabe (left) greets South African President Nelson Mandela in Harare, Zimbabwe, in 1998. The two men have shaped their countries in dramatically different ways.
Former President Barack Obama's tweet after the violence Charlottesville, Va., is now the most-liked tweet ever. The tweet quoted Nelson Mandela and included this photo of Obama visiting a daycare in Maryland.
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Anti-apartheid activist Ahmed "Kathy" Kathrada talks during a tribute to his close friend and former South African President Nelson Mandela at Gandhi Hall on Dec. 8, 2013, in Johannesburg. Kathrada died on Tuesday at 87.
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The study "reveals an intriguing and unexpected observation on the connection between readability and the literary success — that they correlate into the opposite directions."
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Nelson Mandela casts his vote during South Africa's first all-race elections in 1994. Mandela's example led to more democracy across Africa, although overall political freedom has declined on the continent in the last five years.