Computers and the Internet have transformed the way we produce and distribute information and entertainment. And copyright is struggling to keep pace with these changes. The authors of all kinds of works, from the humble email to blockbuster films, rely on copyright to protect what they produce. But authors and those who use their work are often unclear about what copyright allows and what it prohibits. This book was written for those who want to learn about copyright in the 21st century. It explains copyright protection and what it means for copyright holders and copyright users. It also introduces readers to contemporary topics: digital rights management, open licences, software patents and copyright protection for works of traditional knowledge. A final chapter tries to predict how technology will change the publishing and entertainment industries that depend on copyright. The book assumes no special knowledge and avoids technical language as much as possible.