The Hacker Ethic and the Spirit of the Information Age is a book released in 2001, and written by Pekka Himanen, with prologue written by Linus Torvalds and the epilogue written by Manuel Castells.Pekka Himanen is a philosopher. Manuel Castells is an internationally well-known sociologist. Linus Torvalds is the creator of the Linux kernel. The book has the ISBN 978-0-375-50566-9. Source: Wikipedia (en)