Creative Commons is a nonprofit organization that helps foster a collaborative sense of community through the use of various free legal tools--including licenses allowing for the sharing and reuse of creative works and tools to place a work in the Public Domain. All of this is in service of creating a web based environment that makes content easy to find and use.
If you are interested in learning more about Creative Commons, you can visit their website or visit their FAQ page.
Check out these links for more information on Creative Commons:
many of the different license types within Creative Commons require you to include an attribution when using materials under those licenses. Creators earn no money when their work is licensed under Creative Commons and attribution is a way for Creators to promote themselves and their work. There is no one way that you need to format your attribution, so long as it contains the work's Title, Creator, and License type. A simple attribution structure you can rely on when using content from Creative Commons is [Title] by [Creator] is licensed under a [License Type] license.
Here is an example: Say I am using the track "Don't Feed the Clowns" by Calyman. I found it by visiting the site Dig.CCMixter--a web community of Creators sharing and remixing audio under Creative Commons licenses.
When downloading the track, ccMixter tells me the kind of license it uses and also includes plain text and HTML formatted attributions I can simply copy and paste--but even their attributions follow the format mentioned above, with the addition of a URL linking directly to the track's page on ccMixter.
Don't Feed the Clowns by Calyman (c) copyright 2022 Licensed under a Creative Commons Attribution (3.0) license. http://dig.ccmixter.org/files/Lemoneight/65283