How Fiction and Nonfiction

are placed  booksearch  on the shelf

Fiction books

are put on the shelf in alphabetical order

by the author's surname.

eg 826 DAH for a Roald Dahl book


Non-Fiction books

are shelved by their subject's category

eg Cars: 624.6 (You wouldn't worry about the author,

 you would just want the facts about cars)


and non-fiction books are shelved this way so you can easily find the book of your choice.