Preprints are early versions of research papers that have not yet been peer reviewed.
Most publishers are happy to accept publicly available preprints for possible publication in a journal or book. Most also allow submitted manuscripts to be shared at any time on preprint servers.
Nonetheless, it is always worthwhile checking your publisher’s preprint policies prior to submission or deposit, as certain open licences may be discouraged.
Publishers' preprint sharing policies are usually provided on the publisher’s website, or they can be found on the SherpaRomeo deposit policy register.
Preprints are usually shared on dedicated preprint servers.
A discipline-specific preprint server might be the best place to share your work, depending on your field. There are now many well-established preprint servers available in a wide range of disciplines, including in STEMM (science, technology, engineering, mathematics, and medicine) fields and in HASS (humanities, arts, and the social sciences).
Some examples of prominent discipline-specific preprint servers include:
There are also some prominent general, or multi-disciplinary, preprint servers available. These include:
The Directory of Open Access Preprint Repositories (DOAPR) can be used to discover reputable preprint servers in your area. See also Wikipedia's list of academic preprint repositories.
Features of a quality preprint server include:
While each preprint server is slightly different, registering a preprint typically follows similar basic steps. These include: