Gareth Moore (Author) Dr Gareth Moore is the author of a wide range of brain-training and puzzle books for both children and adults, including The Little Book of Puzzles, The Kids' Book of Crosswords, The Brain Workout, Train the Brain and a wide range of other books. He also writes the monthly magazine Sudoku Xtra and runs the puzzle website www.puzzlemix.com. He gained his Ph.D at the University of Cambridge, UK, where he worked on machine intelligence.Ellen Bailey (Author) Ellen grew up in Cambridge and spent her childhood making up games, putting on plays, and writing a magazine for all the children living in her street. After studying English Literature she worked as a children's book editor for a few years before moving into the charity sector. She lives with her husband and baby daughter, and is the author of a variety of bestselling activity books and annuals.