Allows users to create named relationships between each other. It is the basic building block for a social networking site, or any site where users are aware of one another, and communicate.
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Admins create relationship types (friend, coworker, etc). Relationship types can be setup to be one-way or mutual. If a relationship type is one-way (subscriber) only the requester is shown as relating to the requestee. Relationship types can also be set as needing or not needing approval.