XOR and XNOR equivalent?

Question

Why are XOR and XNOR known as "non-equivalent" and "equivalent" gates ?

Answer 1

XOR stands for "eXclusive OR", which means, that the result is true, when AND ONLY WHEN one of the operands is true, but not when both are true or both are false. This means, when only one operand is true and the other is false, they are different meaning non-equivalent.

So XOR is only true, when one operand is true and the other is false.

NXOR stands for "Not XOR", which in short means, it is true for each case when XOR is false and vice versa.

So NXOR is only true, when either both operands are true or both operands are false, meaning when they are equivalent.