Distributing "Romeo and Juliet by William Shakespeare": not plagiarism or copyright violation.

Distributing "Romeo and Juliet by Turing Machine": plagiarism, but not copyright violation.

Distributing "The Lord of the Rings by J.R.R. Tolkien": Copyright violation, but not plagiarism.

Distributing "The Lord of the Rings by Turing Machine": both plagiarism and copyright violation.