The earliest wave of science fiction occurred in the late 19th and very early 20th Century, with novelists such as Jules Verne, H. G. Wells, and Olaf Stapledon writing regularly published hardback books often known by the genre name "scientific romance." The pulp magazine era of circa 1920 - 1950 saw the creation of monthly magazines entirely devoted to what by then was called "science fiction." As the pulp era ended in 1950, some pulp titles transitioned to monthly "digest size," and a large number of new magazine titles appeared in that form. However, the real game changer was the original paperback novel, which began to appear in the late 1940s. A huge fraction of all original paperback novels published in the era 1950 - 1970 were science fiction novels, and the corresponding impact on pseudosciences of the day was huge.