36 Introduction (VI)

We consider a family to be a collection of people affiliated by some connections, such as common ancestors or a common residence. The Simpson family includes a man named Homer and a woman named Marge, the married parents of three sibling children, a boy named Bart and two girls, Lisa and Maggie. This magical family speaks many languages, but most often uses the language of the local television station. In the English-speaking Simpson family, the boy describes his parents as his father and mother and his two siblings as his sisters. In the Spanish speaking Simpson family he refers to his parents as su padre y su madre and his sisters are las hermanas. In the Chinese Simpson family the sisters refer to each other according to their relative ages; Lisa, the elder, as jiě jie and, Maggie, the younger, as mèi mei.^[1]

Kinship relationships are ubiquitous and widely studied, and the names and significance of kinship relations like “is parent of” or “is sibling of” are familiar ones, making kinship a good starting point for understanding relationships in organizing systems.^[2] An organizing system can make use of existing relationships among resources, or it can create relationships by applying organizing principles to arrange the resources. Organizing systems for digital resources or digital description resources are the most likely to rely on explicit relationships to enable interactions with the resources.

In a classic book called Data and Reality, William Kent defines a relationship as an association among several things, with that association having a particular significance.^[3] “The things being associated,” the components of the relationship, are people in kinship relationships but more generally can be any type of resource (Resources in Organizing Systems), when we relate one resource instance to another. When we describe a resource (Resource Description and Metadata), the components of the relationship are a primary resource and a description resource. If we specify sets of relationships that go together, we are using these common relationships to define resource types or classes, which more generally are called categories (Categorization: Describing Resource Classes and Types). We can then use resource types as one or both the components of a relationship when we want to further describe the resource type or to assert how two resource types go together to facilitate our interactions with them.

We begin with a more complete definition of relationship and introduce five perspectives for analyzing them: semantic, lexical, structural, architectural, and implementation. We then discuss each perspective, introducing the issues that each emphasizes, and the specialized vocabulary needed to describe and analyze relationships from that point of view. We apply these perspectives and vocabulary to analyze the most important types of relationships in organizing systems.