Copyright applies to various media, including music, art, and software, not only written works. The video game developer has the copyright for the game's graphics and code.
Pro Tip 2/3
Duration Limit
Copyright protection doesn't last forever. It typically ends 70 years after the creator's death. After the copyright expires, the book becomes public domain.
Pro Tip 3/3
Fair Use Exception
There are exceptions to copyright. 'Fair use' allows limited use, like for education or commentary. Students used the copyrighted song in a classroom presentation, which is fair use.