Looking for good images to use on your project, but you don't want to break any copyright rules? Here are a few great places to go that provide copyright free images.
Unsplash: High quality, modern images. The site says about its work, "All photos published on Unsplash are licensed under Creative Commons Zero which means you can copy, modify, distribute and use the photos for free, including commercial purposes, without asking permission from or providing attribution to the photographer or Unsplash."
Digital Public Library of America list of Select Collections Available for Re-use: The DPLA has created a long list of links to libraries that make their images free for re-use.
Pixabay: A large collection of well-organized photos and videos. The site says about its collection, "All images and videos on Pixabay are released free of copyrights under Creative Commons CC0. You may download, modify, distribute, and use them royalty free for anything you like, even in commercial applications. Attribution is not required."
Public Domain Review Images: A highly curated collection of quirky images. Most the images are quite old, but they're high quality and really interesting.
GIFs released by the National Archives: Copyright-free GIFs! Yes! Find them here!