Preprint

A preprint is a draft of a scholarly or scientific paper that authors share publicly before, or in parallel with, submitting it to a peer-reviewed venue. Preprints are typically deposited on dedicated repositories that permanently host the manuscript and assign it a citable identifier such as a DOI. Informal circulation of preprints predates the internet: in the 1960s the U.S. National Institutes of Health ran biology 'Information Exchange Groups' that distributed manuscripts by mail, a practice that journals successfully shut down after about six years on the grounds that circulated drafts amounted to prior publication. Online preprinting began in earnest with arXiv in 1991, originally for theoretical physics, and later spread to mathematics and computer science. Subsequent servers include SSRN (1994, social sciences), RePEc (1997, economics), bioRxiv (2013, biology), ChemRxiv (2017), and medRxiv (2019, medicine). Preprints sit firmly inside the Green Open Access model: the author retains posting rights, the publisher's subscription paywall is bypassed, and most journals now explicitly permit deposit of the submitted or accepted manuscript. Preprints accelerate dissemination, support priority claims for new results, and create a public record that is independent of any particular journal's acceptance decision. Risks include the absence of formal peer review, which can lead to circulation of erroneous or methodologically weak results; misinterpretation by journalists and the public, particularly visible during the COVID-19 pandemic when preliminary findings were sometimes reported as settled science; and the possibility that an unvetted finding influences clinical or policy decisions. To mitigate these, many servers display prominent 'not peer reviewed' banners and overlay journals such as PCI and Peer Community In provide independent review of preprints before formal publication.