agentic friendships: Voluntary relationships primarily focused on achieving specific practical goals, such as those among peers in a study group or colleagues at work.

communal friendships: Voluntary relationships focused on sharing time and activities together.

cross-category friendships: Voluntary relationships that cross demographic lines.

friendship: A voluntary relationship characterized by intimacy and liking.

friendship rules: General principles for appropriate communication and behavior within friendships, such as keeping a confidence and showing support.

FWB (friends-with-benefits) relationships: Friendships negotiated to include sexual activity but not intended to become romantic attachments.

identity support: Behaving in ways that convey understanding, acceptance, and support for a friend’s valued social identities.

valued social identities: The aspects of your public self that you deem the most important in defining who you are. For example, musician, athlete, poet, dancer, teacher, mother, and so on.