There are three types of images you can use without contacting the owner of the image and asking for permission:

• Images in the public domain. These have no copyright restrictions, so you can use them whenever and however you want.
• Images that have already granted a public license for use. These licenses typically allow you to reuse the image, but some may have additional restrictions, such as no modification, no commercial use, or attribution is required.
• Images without a license for use. These are protected by copyright, so you'll need to argue that you're using "Fair Use", a copyright exception, in order to use the images. There's no clear cut right or wrong answers on whether your image is fair use, but you can learn some guidelines with the resources linked below. You can also email or book an appointment with a librarian for more information.

Images from these sources are in the public domain, can be modified, and do not require attribution.

Images here can be reused, but their licenses may impose some restrictions.