Faculty as authors are granted copyright to their works the second they are "fixed" in a tangible medium. This essentially means as soon as the author types, copyright is applied to the created work. The rights grated by copyright means that the author has the exclusive rights of -
The author also has the right to transfer these rights to others. Most often author's transfer these rights to a publisher in exchange for having them published. This is often done without fully realizing that any use of the work they created would then be the same for them as any other user. Thereby limiting their use to make their own work available on their own website or other systems like Academia.edu or ResearchGate.net. It can also limit the use within their classroom teaching or to use charts and figures in later works. It also limits their ability to make their scholarship available through Institutional Repositories or Subject Based Repositories such as arXive.
It has also been shown that the wider the scholarly work is disseminated or the more available it is, the more likely it is to be read and used. Therefore, libraries and academic institutions encourage faculty authors to be aware of their rights as authors and creators of copyrighted works and to attempt to retain those rights that are important to them. There are numerous strategies for negotiating to retain the authors rights when dealing with publishers but one of the simplest and most effective is the use or inclosing of and Author Addendum to copyright transfer agreement. This is essentially an addition to the contract between the author (you) and the publisher outlining what rights you would like to retain. As most of these rights do not seriously negatively impact the ability of the publisher to use the article, they are often accepted when needed. The rise in use of these amendments have moved many publishers to adapt their copyright transfer agreements to automatically grant the rights for certain uses such allowing use for the authors work in their course or course packs for their courses.
The SHERPA/RoMEO database of publishers and their copyright agreements is a quick place to determine in the policies of the journal you may be interested in publishing your research.
The transfer of copyright in liu of allowing for publication is a negotiation between you and the publication, so you will need to determine what rights are important as well as how important they before negotiating with the publisher. The decision ultimately lies with the faculty author as they hold the copyright until such time that it is transferred.
The following links discuss ways to retain rights granted to authors under copyright to authors rather than simply transferring rights to the publisher. Although some publishers will not accept these addendums, many association and non-profit publishers as well as some commercial publishers realize that the faculty should be able to retain certain rights such as using their own works within their courses.
SPARC Author Addendum Information. SPARC®, the Scholarly Publishing and Academic Resources Coalition, is an international alliance of academic and research libraries working to create a more open system of scholarly communication.
Scholar's Copyright Addendum Engine from Creative Commons will help you generate a PDF form that you can attach to a journal publisher's copyright agreement to ensure that you retain certain rights.