Prince William and Kate have named their new-born baby boy George Alexander Louis, William's office said on Wednesday (July 24).
The baby, third in line to the British throne, will be known as His Royal Highness Prince George of Cambridge, Kensington Palace said in a statement.
On Tuesday (July 23) the couple gave the world its first glimpse of their new baby when they left hospital to a barrage of camera flashes.
The couple followed tradition by giving the public the first sight of the baby on the steps of the hospital as they left - just as William's father Prince Charles and late mother, Princess Diana, did with him.
The baby is third in line to the throne after grandfather Charles and William, 31, and pushes the fun-loving Prince Harry, William's brother, into fourth place.
George has been the name of six British kings. The last, George VI, was the father of Queen Elizabeth and reigned from 1936 to 1952.
Presented by Adam Justice