The private circulation of preprints, as they are called, is standard practice in physics, since fellow researchers don’t want to wait until a paper is published to study it. In some fast-moving fields, the preprint - now frequently distributed electronically - is the principal means of communication. The published paper becomes, so to speak, a record for the file.
(emphasis added)
John Wheeler, Geons, Black Holes, and Quantum Foam, 1999, Norton & Co.: New York