A thumbnail is
|“||[a] miniature representation of a page or an image used to identify a file by its contents. Clicking the thumbnail opens the file. Thumbnails are an option in file managers, such as Windows Explorer, and they are found in photo editing and graphics program to quickly browse multiple images in a folder.||”|
Generally, a website will use a thumbnail as a reference device, and embed a link in the image, which will, in turn, send a user to a high resolution, full scale version of the image. When used for this purpose, a thumbnail of an image may potentially infringe on a number of exclusive rights, including the reproduction, distribution, and public display rights, and, arguably, the right to make derivative works.