How many books are lord of the rings?
No context provided
How many books are part of The Lord of the Rings' internal structure?
six
Although generally known to readers as a trilogy, the work was initially intended by Tolkien to be one volume of a two-volume set, the other to be "The Silmarillion", but this idea was dismissed by his publisher. For economic reasons, "The Lord of the Rings" was published in three volumes over the course of a year from 29 July 1954 to 20 October 1955. The three volumes were titled "The Fellowship of the Ring", "The Two Towers" and "The Return of the King". Structurally, the novel is divided internally into six books, two per volume, with several appendices of background material included at the end. Some editions combine the entire work into a single volume. "The Lord of the Rings" has since been reprinted numerous times and translated into 38 languages.
In how many books (volumes) was The Lord of the Rings initially published?
three
The Lord of the Rings
The Lord of the Rings
https://en.wikipedia.org/wiki/The%20Lord%20of%20the%20Rings
 the story began as a sequel to Tolkien's 1937 children's book The Hobbit, but eventually developed into a much larger work. 
The Lord of the Rings
Although generally known to readers as a trilogy, The Lord of the Rings was initially intended by Tolkien to be one volume. For economic reasons, The Lord of the Rings was published in three volumes over the course of a year. The three volumes were titled The Fellowship of the Ring, The Two Towers and The Return of the King. Structurally, the novel is divided internally into six books, two per volume, with several appendices of background material included at the end. The Lord of the Rings originally began as a sequel to Tolkien's 1937 children's book The Hobbit but eventually developed into a much larger work. 