Sir Terry Pratchett (1948-2015) was an English author best known for his Discworld series of fantasy novels. He wrote more than 70 books, selling over 85 million copies worldwide in 37 languages. Pratchett was a master of satire, blending humor and social commentary in his work. He was knighted in 2009 for his services to literature. Pratchett was diagnosed with Alzheimer's disease in 2007 and became a prominent advocate for the right to die with dignity. He passed away in 2015, leaving behind a legacy of beloved characters and stories that will live on for generations.