What is a preprint?

A preprint is a version of a research paper that its authors share publicly before, or alongside, peer review, on a server such as arXiv, bioRxiv, medRxiv or SSRN. Preprints make research free to read and fast to share. They haven’t necessarily been peer-reviewed, so check whether a published version exists and what changed.

An accepted manuscript, or postprint, is the peer-reviewed text before the publisher’s formatting.

Many fields, from physics to machine learning, read preprints first.