Nelson Mandela’s 95th birthday in hospital, as events take place around the world and in South Africa in his honor.
South Africans are being urged to match the former president and anti-apartheid leader’s 67 years of public service with 67 minutes of charitable acts.
Mr. Mandela, who is in critical but stable condition with a recurring lung infection, entered hospital on 8 June.
His daughter Zindzi said on Wednesday that he had made “dramatic progress”.
“I should think he will be going home anytime soon,” she told foreign media.
Mr. Mandela’s birthday is also Nelson Mandela International Day, a day declared by the UN as a way to recognize the Nobel Prize winner’s contribution to reconciliation.
The former statesman is revered across the world for his role in ending apartheid in South Africa. He went on to become the first black president in the country’s first all-race elections in 1994.
The ruling African National Congress (ANC) said that on this Mandela Day homage was being paid to 95 years of “life well-lived”, dedicated to the liberation of South Africans and people all over the world.
The day kicks off with millions of school children across South Africa singing Happy Birthday to Mr. Mandela.
To mark the former statesman’s 67 years as a lawyer, activist, prisoner and president, volunteers will spend 67 minutes renovating schools and orphanages, cleaning hospitals and distributing food to the poor.
African President Zuma plans to mark the occasion by overseeing the donation of houses to poor white families in the Pretoria area.
In events taking place internationally, with an image of a large Mandela painting by South African artist Paul Blomkamp featured in New York’s Times Square.
British entrepreneur Richard Branson has pledged 67 minutes of community service on Thursday to “make the world a better place, one small step at a time”, speaking in a recorded message.
Meanwhile, concerts are planned later this week in the Australian city of Melbourne, featuring local and African artists.
His illness gives extra poignancy to this year’s Mandela Day, correspondents say.
As the family and millions around the country reflect the role Mr. Mandela played in South Africa, there will be a quiet prayer that he will return home soon.
The latest reports from family members indicate that Mr. Mandela’s condition may have improved.
His third wife, Graca Machel, said last Friday that she was “less anxious” about his health than before and that he was continuing to respond well to treatment.
Today also is the 15th anniversary of the couple’s marriage.