If you don't know, don't use it!
Copyright ensures that authors and artists receive proper credit and compensation if their works become best-sellers or popular hits...just examples. Copyright protects creators even if the work isn't published.
Copyright material is the term given to any existing material that belongs to somebody else, such as the following:
You cannot copy, manipulate, reuse, or distribute a copyrighted work without permission from the copyright holder, who might (should) charge a fee.
Permission relates to any material your project uses, which may include the following:
There are a few loopholes but we regress on Fair Use law, and other topics.