Here are some great websites for obtaining free content that you do not create yourself!
Pictures:
Public Domain (do not need to credit)
Sound Effects:
Public Domain (do not need to credit)
Creative Commons (check license)
Music:
Creative Commons (must credit artist or site)
http://dig.ccmixter.org/ (music/credit)
http://bensound.com/ (music/credit)
Videos:
Public Domain (do not need to credit)
Here is some helpful information for further research:
U.S. Copyright Office Fair Use Index
Fair Use Frequently Asked Questions
A Writer's Guide to Permissions and Fair Use
Copyright is a form of protection provided by U.S. law to creators of original works of authorship. An original work of authorship is copyrighted the moment it is fixed in a tangible form of expression—be it paper or digital, published or unpublished.
It is absolutely crucial that we make sure all content creators' works are respected.
Most of the time, any music, pictures, or videos not created by your project's team can only be used with written permission from those creators. In the United States, copyright goes into effect as soon as a work is created.
Some media falls under what's known as Fair Use -- this means that there are times when using copyrighted material can be used for educational purposes or parody, as long as you're only using enough of the media to make a point, and you cite the material. If you utilize media as fair use, you need to make sure whatever you want to use can be argued as fair use.
Some things in your shots, such as billboards, or logos on clothing of people who walk by, are generally not pursued by content creators, as those things are normally out of your control.
There is also media in the Public Domain, which is free for anyone to use without crediting.
Always be mindful about using any media or logos in your projects.
Check out this great video from Common Sense Education:
To find out more information on how copyright works check out the topics below:
Fair Use is a limitation on a copyright holder's exclusive rights to reproduce, distribute, make derivative works, and perform or display their work. It is an interpretation of one's use of copyrighted material, where the benefits of use outweigh the exclusive rights of the copyright holder.
Resources to help you determine if using is fair or not:
https://www.copyright.gov/fair-use/more-info.html
https://copyright.columbia.edu/basics/fair-use.html
The Public Domain is the term used to describe the set of works not protected by copyright law. It is the name for those works that are held in common by the public and can be used freely as a resource for new knowledge.
A work is in the public domain if it is no longer under copyright protection or if it does not meet the requirements for copyright protection.
The Public Domain includes:
1. Works published in the U.S. prior to 1923.
2. Works whose copyright has expired or was not renewed.
3. Works which do not qualify for copyright protection.
4. Works created by U.S. Government employees in the scope of their employment.
Resources to help you determine if media is in the Public Domain:
https://fairuse.stanford.edu/overview/public-domain/welcome/
https://copyright.cornell.edu/publicdomain
Creative commons is an organization devoted to expanding the creative content available for others to legally build upon and share. There are four different licenses under creative commons which each have different conditions.
1. Attribution
You are able to share, meaning copy and redistribute, and adapt, meaning remix, transform or build upon, the content. As long as you give appropriate credit, provide the link and state if changes were made.
2. Attribution-ShareAlike
Under this license you have the same freedoms as the Attribution license. The only difference is that, if you adapt the content in any way, you MUST distribute your contributions under the same license as the original.
3. NonCommercial
Under this license you have the same freedoms as the Attribution license. The only difference is you may not use the material for commercial purposes.
4. NoDerivatives
Under this license you can only share the material. If you remix, transform, or build upon the content, you may not distribute the modified material.
Resources to help you determine which license your media is under:
https://creativecommons.org/share-your-work/licensing-types-examples/