Many art and art history courses involve finding images. While many students use image tools and collections available freely online, there are other resources that are only available by subscription databases like Artstor.
Art and art history courses ask you to find background materials or discussion of the art. You can find written articles about art in newspapers, magazines, museum websites, blogs and other places, but if you need specialized information like discussions of techniques, historical context, comparisons to other art genres or academic viewpoints on art, you should plan to search research databases. Like these below.