Final answer:
The type of page used to print thumbnails of photos by proprietary software is called a contact sheet, which aids in reviewing and organizing images.
Step-by-step explanation:
The special type of page typically allowed by proprietary software packages to print single photos or groups of them is known as a contact sheet. A contact sheet is a photographic print containing thumbnails of all the images from a film roll or digital photo collection, often used by photographers to quickly review multiple shots. It is especially helpful for identifying and organizing photos before selecting which ones to print in larger formats.