Preprint

Traditionally, a preprint is a copy of a manuscript (or "paper") which is distributed to interested colleagues after it was submitted for publication, but before it is actually printed, but it can also be a draft manuscript which is not yet in its final form. Originally, preprints were mimeographed copies or even only carbon copies, while now they usually are electronic documents. One must, however, be aware of an important difference between a preprint and a published manuscript. A preprint has not undergone the peer review process one may expect from established publishing houses. (Printed copies of the published paper are called reprints.)

Many authors use the possibilities of the internet to make their preprints freely available on their homepages or on dedicated preprint servers where they are archived and stay permanently available. For commercial reasons, some scientific publishers try to prohibit this practice for their authors.

An important example of such a preprint server is arXiv.org (which is dedicated to Physics, Mathematics, Computer Science, Quantitative Biology, Quantitative Finance and Statistics). Among its documents, now called e-prints there are no longer only true "preprints", but also often manuscripts – even important ones – which are not and will not be "printed" elsewhere.