Copyright
Anyone who takes a photo or creates their own original artwork, and posts it online, has the right to be acknowledged as the creator of that image. They automatically own the copyright for that photo, which means that legally, they have the right to decide where and how that image can be used. If you use an image that is copyrighted, you’re breaking the law. You need to get the author’s permission first.
Creative Commons
The copyright holder of an image can choose to make their work available using a variety of Creative Commons (CC) licenses. Essentially, these allow photos to be re-used without handing over the full copyright.
But the author does get to decide how they want their work to be re-used – e.g. Can the photo be changed? Can it be used for commercial gain (for example in an advertising campaign)? Does the author need to be credited?
There are 6 types of CC license:
Anyone who takes a photo or creates their own original artwork, and posts it online, has the right to be acknowledged as the creator of that image. They automatically own the copyright for that photo, which means that legally, they have the right to decide where and how that image can be used. If you use an image that is copyrighted, you’re breaking the law. You need to get the author’s permission first.
Creative Commons
The copyright holder of an image can choose to make their work available using a variety of Creative Commons (CC) licenses. Essentially, these allow photos to be re-used without handing over the full copyright.
But the author does get to decide how they want their work to be re-used – e.g. Can the photo be changed? Can it be used for commercial gain (for example in an advertising campaign)? Does the author need to be credited?
There are 6 types of CC license:
Whenever you use an image that has a Creative Commons license, you have to credit the author. This is a “moral right” even outside copyright law.
Stock photography
Stock photography refers to photographs that are published online with the purpose of being shared and used. These photos are often taken by professionals and can be purchased and used. They range from expensive sites such as Getty Images, iStock, and Shutterstock, to sites where images can be used at no cost, such as Flickr Creative Commons, Pixabay, Unsplash, Foter, Pics4Learning, and ClipSafari.
Adapted from https://intercom.help/bookcreator/en/articles/4163730-understanding-copyright-licensing-and-attribution-for-photos-and-images