Binary relation
Types of binary relations

Some important types of binary relations R {\displaystyle R} over sets X {\displaystyle X} and Y {\displaystyle Y} are listed below.

Uniqueness properties:

Totality properties (only definable if the domain X {\displaystyle X} and codomain Y {\displaystyle Y} are specified):

Uniqueness and totality properties (only definable if the domain X {\displaystyle X} and codomain Y {\displaystyle Y} are specified):

If relations over proper classes are allowed:
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