What are Scientific Preprints?
Preprints are early versions of journal articles before they have gone through the peer-review process and been officially published. As the peer review process can take over a year, preprints are a good source of very current research but they have not gone through peer-review. Thus you must evaluate each article more carefully before using.
What is Peer review?
Peer review is a process in which experts in the field analyze and evaluate a journal article or conference proceeding based on the research methods, research conducted, conclusions and overall quality of the article before it is accepted for publication.
What are E-prints?
E-prints are scientific or technical documents exchanged electronically to facilitate communication of new research among scientists and researchers. E-prints include technical communications and scholarly papers that have been submitted for publication. E-prints may or may not have gone through the peer-review process. See also Gray Literature
Note: There may be multiple versions of an article including retractions, addendum, and comments.