Did you know that you may not own the copyright to your published works? In the traditional publishing model, authors sign an agreement that transfers most, if not all, of their author rights over to the publisher. This agreement limits what you may do with your work:
Preprint: A preprint is the original version of the manuscript as it is submitted to a journal. Usually, these are .doc files with minimal formatting or typesetting.
Postprint: A postprint is a manuscript that has gone through the peer review process, but has not yet been subjected to the final copyediting, formatting, and typesetting by the publisher. Usually, post-prints look like .doc files. Sometimes this version is referred to as the accepted manuscript version.
Version of Record: The version of record, sometimes called the publisher's version or final version, is the version that is published on the publisher's website. It is professionally formatted and looks more professional than preprints or postprints. Himmelfarb Library links to the Versions of Record via DOIs and "Find It @ Himmelfarb" links in the catalog.
Many publishers allow authors to share and self-archive preprints and postprints, sometimes after a period of embargo. An embargo is a period of time required by the publisher where access to the archived version is restricted until after the embargo period expires.
However, every publisher is different, and sometimes publishers have varying policies for different journals under their umbrella, so you should always check before you post. The copyright transfer agreement that authors sign before publishing is the best place to find this information. SHERPA/RoMEO, a database that collects information about publisher and journal copyright and self-archiving policies, is a good source of information. It is advised that you double check the publisher's webpage, as the information in SHERPA/RoMEO is sometimes out of date or incorrect.
Author agreements can oftentimes be negotiated. Read over the agreement carefully.