Cartesian product

The Cartesian product of two sets $A,B$ , denoted by $A\times B$ , is the set of all possible ordered pairs whose first component is an element of $A$ and whose second component is an element of $B$ .

Definition
Given two sets $A,B$ , $A\times B={\Big \{}(x,y)|x\in A\land y\in B{\Big \}}$

Example

Suppose $A=\{0,1\}$ and $B=\{a,c\}$ :

$A\times B={\Big \{}(0,a),(0,c),(1,a),(1,c){\Big \}}$