Has the time come for preprints in biology?

Preprints, non–peer-reviewed drafts of manuscripts available on the Internet, have been used in conjunction with peer review and publication in journals in the physical sciences for almost 25 years. Recently, more scientists have been discussing whether preprints can play a similar role in biological and biomedical research. Here, I discuss my excitement and concerns about the role that preprints can play in disseminating research findings in the life sciences.