The statement images may be subject to copyright means that a collection of pictures may have legal restrictions on when they can be used without permission. This means that if you see this statement, you should assume that the images are protected by copyright and that you need to obtain permission from the copyright owner in order to use them. It is important to note that all types of visual art, including photographs, digital art, infographics, maps, charts, paintings, and more, are subject to copyright. The specifics of image copyright laws can vary among countries, but most countries are members of the Berne Convention treaty, which sets basic copyright standards.