Interest graph

They can be used as indicators of various aspects, such as a person's preferences regarding activities, purchases, destinations, as well as who they may choose to meet, follow, or support politically.

They can be applied in conjunction with social graphs as a way to meet or connect with people in a social network or community with shared or common interests, and who may not otherwise know each other.

[7][13] Interest graphs can also be applied to marketing for purposes such as audience analytics and audience-based buying,[14] for sentiment analysis,[15] and for advertising as another form of behavioral profiling and targeting based on interests.

[16] Interest graphs may be applied to product development by using customer interests to help determine which new features or capabilities to provide in future versions of a product.

[5] Interest graphs have many other uses as well,[12] including simulation,[17] research and other content discovery and filtering tasks,[18] as input to recommendation engines for films, books, music, etc.,[19] and for learning and education.

Suppose two people have similar interests, such as photo and they like the same music. So there is a relationship between them based on their interests which can be shown by interest graph. Vertices correspond to entities, and edges are the relationships between entities.
Red edges are the part of an interest graph, where relations (red edges) could be between (1) user and interest and (2) between users. Blue edges are the part of a social graph , where there are relations only between users.