Doyle appeared to be a workaholic when it came to Sherlock Holmes, writing four novels and 56 short stories (which have been collected in a further five anthologies). The 60 official stories represent the entirety of the official Sherlock Holmes canon, although there have been many unofficial works since. The works not written by Doyle are known as extracanonical works. The delineation is not always clear, with some contending that a few of the extracanonical works are as good as what Doyle had written, and ought to be a part of the main canon. While that is unlikely to happen, as Sherlock Holmes (the character) is in the public domain, the unofficial canon will only grow with time.