In set theory, the intersection of two sets ${\displaystyle A, B}$ is the set of all elements in ${\displaystyle A}$ that also belong in ${\displaystyle B}$ .

If the intersection of two sets is empty, then the two sets are disjoint.

Example

Suppose ${\displaystyle A=\{a,b,f,g\}}$ and ${\displaystyle B=\{b,c,d,g\}}$ .

${\displaystyle A\cap B=\{b,g\}}$

See also

• Logical conjuction (Equivalent in logic)
• Complement (set theory)
• Union (set theory)
• Symmetric difference