Thumbnails are interactive small versions of images. The thumbnail itself can represent an image or a still from a video. Clicking on a thumbnail can lead to a new page, open the full-size image into a lightbox, or otherwise display the selected image.

Thumbnails are often used for two reasons: helping users scan the content and reducing the page loading time. To reduce the data the server needs to load, create separate thumbnail assets instead of shrinking full-size images.