: Stock sites that generate temporary filenames for thumbnails or previews.

: Specific collections that use unique ID strings for their database.

This specific naming convention—often consisting of a prefix like "sub" followed by a long string of numbers—is typically used for by specific organizations, such as:

(e.g., a historical figure, a specific landscape, or a piece of art).

(e.g., a specific website, a textbook, or a photo agency).

: Private asset management systems used by publishers.