LONDON (AP) -- Fantasy author Terry Pratchett has been knighted by Queen Elizabeth II for services to literature.

The British writer received the knighthood at an ceremony at Buckingham Palace Wednesday wearing a top hat and morning suit.

The 60 year old British writer is known for his "Discworld" series of novels and has sold more than 55 million books worldwide. He announced last year that he has early onset Alzheimers — a rare form of the disease.

A 14-year-old swimmer who won two gold medals at the 2008 Paralympic Games was also made a Member of the Order of the British Empire or MBE in Wednesday's ceremony. The British government said Eleanor Simmonds is the first person under 18 to receive the award.