A list of pairs of elements of given domains that are related to each other.

Defined by

relation (optional attributes) of (domain1 * domain2 * ...)

They can be explicitly defined using tuples (of the same type) as

letting R be relation((1,1,0),(1,0,1),(0,1,1))

Relations have two groups of attributes

  1. cardinality related

  2. Binary Relation (only on relations that contain 2 identical domains)

See this demonstrated here.