A collection of essays and other non fiction from Terry Pratchett, spanning the whole of his writing career from his early years to the present day.      Terry Pratchett has earned a place in the hearts of readers the world over with his bestselling Discworld series -- but in recent years he has become equally well-known and respected as an outspoken campaigner for causes including Alzheimer's research and animal rights. A Slip of the Keyboard brings together for the first time the finest examples of Pratchett's non fiction writing, both serious and surreal: from musings on mushrooms to what it means to be a writer (and why banana daiquiris are so important); from memories of Granny Pratchett to speculation about Gandalf's love life, and passionate defences of the causes dear to him.