Sir Terence David John Pratchett, OBE (born 28 April 1948), more commonly known as Terry Pratchett, is an English novelist, known for his frequently comical work in the fantasy genre. He is best-known for his popular and long-running Discworld series of comic fantasy novels. Pratchett's first novel, The Carpet People, was published in 1971, and since his first Discworld novel (The Colour of Magic) was published in 1983, he has written two books a year on average.

Pratchett was the UK's best-selling author of the 1990s, and as of August 2010 had sold over 65 million books worldwide in thirty-seven languages

He is currently the second most-read writer in the UK, and seventh most-read non-US author in the US. In 2001 he won the Carnegie Medal for his young adult novel The Amazing Maurice and his Educated Rodents.

Pratchett was appointed Officer of the Order of the British Empire (OBE) "for services to literature" in 1998. In addition, he was knighted in the 2009 New Year Honours. In December 2007, Pratchett publicly announced that he was suffering from early-onset Alzheimer's disease, subsequently making a substantial public donation to the Alzheimer's Research Trust, and filming a programme chronicling his experiences with the disease for the BBC.

Pratchett was born in 1948 in Beaconsfield in Buckinghamshire, England, the only child of David and Eileen Pratchett, of Hay-on-Wye. His family moved to Bridgwater, Somerset briefly in 1957, following which he passed his eleven plus exam in 1959, earning him a place in John Hampden Grammar School. Pratchett described himself as a "non-descript student", and in his Who's Who entry, credits his education to the Beaconsfield Public Library.

His early interests included astronomy; he collected Brooke Bond tea cards about space, owned a telescope and desired to be an astronomer, but lacked the necessary mathematical skills. However, this led to an interest in reading British and American science fiction. In turn, this led to attending science fiction conventions from about 1963/4, which stopped when he got his first job a few years later. His early reading included the works of H. G. Wells and Arthur Conan Doyle and "every book you really ought to read" which he now regards as "getting an education".

At age 13, Pratchett published his first short story "The Hades Business" in the school magazine. It was published commercially when he was 15.

Pratchett earned 5 O-levels and started A-level courses in Art, English and History. Pratchett's first career choice was journalism and he left school at 17 in 1965 to start working for the Bucks Free Press where he wrote, amongst other things, several stories for the Children's Circle section under the name Uncle Jim. One of these episodic stories contains named characters from The Carpet People. These stories are currently part of a project by the Bucks Free Press to make them available online. While on day release he finished his A-Level in English and took a proficiency course for journalists.

Pratchett had his first breakthrough in 1968, when working as a journalist. He came to interview Peter Bander van Duren, co-director of a small publishing company. During the meeting, Pratchett mentioned he had written a manuscript, The Carpet People. Bander van Duren and his business partner, Colin Smythe (of Colin Smythe Ltd Publishers) published the book in 1971, with illustrations by Pratchett himself. The book received strong, if few reviews. The book was followed by the science fiction novels The Dark Side of the Sun and Strata, published in 1976 and 1981, respectively.

After various positions in journalism, in 1980 Pratchett became Press Officer for the Central Electricity Generating Board in an area which covered three nuclear power stations. He later joked that he had demonstrated "impeccable timing" by making this career change so soon after the Three Mile Island nuclear accident in Pennsylvania, USA, and said he would "write a book about his experiences, if he thought anyone would believe it".