Originally titled "The Appeal's Pocket Series," the first print run of "Little Blue Books" contained 36 titles published in 70 books. The series went through several names, adding titles each time. When it was finally named "Little Blue Books," there were over 1900 titles and many more actual books.
The books were 3 1/2 by 5 inches, a size that Emmanuel Haldeman-Julius, the publisher of the books, determined was small enough to readily fit in a regulation-sized pocket. His intent in creating the "Little Blue Book" series was to bring new ideas, view points and common knowledge to as many people as possible.