A Cayley table, also called an operation table, displays a binary operation on a finite set. If the set is 
and the operation is 
, the entry in row 
and column 
is 
.
For a finite group, every group element occurs exactly once in each row and column of its Cayley table, so the table is a Latin square. Conversely, an operation table describes a group precisely when its group operation has an identity element, every group element has an inverse element, and the operation is associative.
