What is Palme d'Or, award presented to Robert De Niro at Cannes?

The Palme d'Or is the highest prize awarded at the Cannes Film Festival. Although the festival began in 1946, the Palme d'Or was introduced in 1955. A film that wins the Palme d'Or cannot receive any other award, as it is considered the highest prize across all categories. This year, actor-director Robert De Niro was presented the award.