0_Apprentice
I've been looking into reading the other books from the Lord of the Rings universe that Tolkien wrote. Where should I start?
1_Wizard
The Lord of the Rings is fantastic. It is an by an Engish novel by JRR Tolkein.
0_Apprentice
Can you tell me what I should read if I want to learn more about the history of that written universe? I think the name of it starts with an s.
1_Wizard
Seeing that I have only read The Lord of the Rings I am only knowledgeable on this very subject. I do know it was a sequel to "The Hobbit".
0_Apprentice
I wonder how The Hobbit was made into three separate full length films even though it was just one book.
1_Wizard
You could ask someone that is knowledgeable about "The Hobbit". Since you are so curious about The Lord of the Rings, it has sold over 150 million copies. 
0_Apprentice
Where does that put it on the list of best-selling book series of all time?