A postprint is a digital draft of a research journal article after it has been peer reviewed and accepted for publication, but before it has been typeset and formatted by the journal.
Example of a page from an eNeuro accepted manuscript, 2019
Open access (OA) is a set of principles and a range of practices through which research outputs are distributed online, free of access charges or other barriers. With open access strictly defined, or libre open access, barriers to copying or reuse are also reduced or removed by applying an open license for copyright.
Authors may use form language like this to request an open access license when submitting their work to a publisher.