What is the author's style in the novel, Unbreakable?

The book is written for a young adult audience. Most of the language is modern with many popular and slang terms. This may tend to 'date' the book as it ages. However, it is highly relevant to those reading the material presently. The use of engineered and nonsense words is also employed by the author, such as names of sci-fi like weaponry, ancient writings, names of places, and legends.