Proper nouns are the names of specific people, places, things or ideas. Beowulf is an example of a proper noun as it is the name of a specific character. The document provides context about the story of Beowulf and defines what a proper noun is, giving examples like character names from the story like Beowulf, Hrothgar, and places. It encourages identifying and highlighting the proper nouns when reading the first paragraph of the story.