Hotlinking is an expression that describes the inclusion of images on a given website via direct links. If you have site A, for example, and a person creates website B and wishes to include a couple of images from your site, they are able to either save the images and then add them on their site or they could simply place links on their website to the images on yours. As a result, whenever a visitor opens website B, site B will steal traffic from your own site A, because the images shall load from your website hosting account. This approach is sometimes used for documents and other types of files also. If you would like to prevent 3rd parties from stealing your content and from using your own website hosting account’s resources, you could limit their capability to use direct links to your files on their sites.