The Nebula Awards annually recognize the best works of science fiction or fantasy published in the United States during the previous year. The awards are organized and awarded by the Science Fiction and Fantasy Writers of America (SFWA), a nonprofit association of professional science fiction and fantasy writers. They were first given in 1966 at a ceremony created for the awards, and are given in four categories for different lengths of literary works. A fifth category for film and television episode scripts was given 1974–78 and 2000–09. The rules governing the Nebula Awards have changed several times during the awards’ history, most recently in 2010. The Nebula Awards have been termed as one of “the most important of the American science fiction awards”. Winning works have been published in special collections, and winners and nominees are often noted as such on the books’ cover. SFWA numbers the awards by the year prior to the year the award is given in; the 2012 awards were presented in San Jose, California on May 18, 2013, and the 2013 awards were presented in San Jose, California on May 17, 2014.