Finding Nonexlusively Licensed and Public Domain Images
These images can generally (always read the fine print) be incorporated into noncommercial multimedia projects, even those being published on the web, so long as full credit is given to the creator in a footnote or elsewhere. However, for use in publications from which any proceeds will be derived, permission will probably need to be sought from the copyright holder.
Finding Images on the Web (Mostly Copyrighted)
Most images found on the web are still under copyright. More to the point, the copyright holders as a rule have not given blanket permission for their work to be reproduced, even for non-commercial use. As such, permission should probably be requested from the copyright holder on a case-by-case basis for any use beyond the classroom and arguably educational conferences.
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