An operation * is said to be commutative if x*y = y*x for all x and y.
Two elements x and y of a set S are said to be commutative under a binary operation * if they satisfy x*y = y*x. Real numbers are commutative under addition x + y = y + x and multiplication x·y = y·x. The Wolfram Language attribute that sets a function to be commutative is Orderless.
Orderless
elementary school level (California grade 2 standard)