Question: Which fantasy book series, with more than 80 million books sold in 37 languages, was written by Only You Can Save Mankind author Terry Pratchett?

Context articles: The Streets of Ankh-Morpork
List of programmes broadcast by Sky 1
Johnny and the Bomb
Terry Pratchett First Novel Award
Johnny and the Dead
Only You Can Save Mankind
Journey to Alpha Centauri (In Real Time)
Tina Hannan
Discworld
Terry Pratchett's The Colour of Magic

The Streets of Ankh-Morpork is a brief guide and map of the fictional city of Ankh-Morpork in Discworld, a fantasy series by English author Terry Pratchett.
 The final, artwork-grade map was drawn by Stephen Player, who also drew the artwork for a later publication, "The Discworld Mapp".
Sky 1 has commissioned many homegrown programmes since it first started broadcasting back in 1984 but it was not until 1989 that content went beyond music and children's reprogramming.
 During the early years new game shows included a few series of "Blockbusters" and "Spellbound", along with "The Price is Right" and "Sale of the Century".
 Original dramas include "Dream Team", a series based on a fictional football team; "The Strangerers", a science fiction sitcom that was dropped after one series and never repeated; Al Murray's sitcom "Time Gentlemen Please"; and "Baddiel's Syndrome". "
Hex", another sci-fi show, proved popular but was cancelled in April 2006, and "Mile High" also proved quite popular but only lasted from 2003–2005.
 Sky One commissioned "Terry Pratchett's Hogfather" for Christmas 2006, which proved to be their most successful programme ever.
 Following that success, Sky brought out in 2008 an adaptation of "The Colour of Magic" and its second half "The Light Fantastic", and in 2010 "Terry Pratchett's Going Postal", the 33rd book in the "Discworld" series.
 Sky also co-produces "The 4400" and co-financed the first season of "Battlestar Galactica".
Johnny and the Bomb is a 1996 novel by Terry Pratchett.
 It is the third novel to feature Johnny Maxwell and his friends, and deals with the rules and consequences of time travel.
 The first two novels in the "Johnny Maxwell Trilogy" are "Only You Can Save Mankind" (1992) and "Johnny and the Dead" (1993).
The Terry Pratchett First Novel Award is a biennial award for the best unpublished science fiction novel in the Commonwealth of Nations.
 It is named after British author Terry Pratchett.
 The book is chosen by a panel of judges previously including Pratchett.
Johnny and the Dead (1993) is the second novel by Terry Pratchett to feature the character Johnny Maxwell.
 The other novels in the "Johnny Maxwell Trilogy" are "Only You Can Save Mankind" (1992) and "Johnny and the Bomb" (1996).
 In this story, Johnny sees and speaks with the spirits (they object to the term "ghost") of those interred in his local cemetery and tries to help them when their home is threatened.
Only You Can Save Mankind (1992) is the first novel in the Johnny Maxwell trilogy of children's books and fifth young adult novel by Terry Pratchett, author of the "Discworld" sequence of books.
 The following novels in the "Johnny Maxwell Trilogy" are "Johnny and the Dead" (1993) and "Johnny and the Bomb" (1996).
 The setting of the novels in the modern world was a departure for Pratchett, who writes more regularly in fantasy world settings.
Journey to Alpha Centauri (In Real Time) is an interactive fiction game by Julian Fleetwood released in 1998.
 It has the longest video game minimum completition time – slightly more than three thousand years.
 It has never been (and in all likelihood will never be) completed without cheating.
 It was inspired by a description of a similar game in Terry Pratchett's novel "Only You Can Save Mankind".
Tina Hannan is a London-based writer and photographer, noted for the book "Nanny Ogg's Cookbook", co-written with fantasy author Terry Pratchett in association with Stephen Briggs and Paul Kidby as a companion to the Discworld series.
 Hannan, then working in a public house in Berkshire, provided the recipes for the work.
Discworld is a comic fantasy book series written by the English author Terry Pratchett (1948–2015), set on the fictional Discworld, a flat disc balanced on the backs of four elephants which in turn stand on the back of a giant turtle, Great A'Tuin.
 The books frequently parody or take inspiration from J. R. R. Tolkien, Robert E. Howard, H. P. Lovecraft, Charles Dickens, and William Shakespeare, as well as mythology, folklore and fairy tales, often using them for satirical parallels with current cultural, political, and scientific issues.
 The series is popular, with more than 80 million books sold in 37 languages.
Terry Pratchett's The Colour of Magic is a two-part television adaptation of the bestselling novels "The Colour of Magic" and "The Light Fantastic" by Terry Pratchett.
 The fantasy film was produced for Sky1 by The Mob, a small British studio, starring David Jason, Sean Astin, Tim Curry and Christopher Lee as the voice of Death.
 Vadim Jean both adapted the screenplay from Pratchett's original novels, and served as director.