) A Boolean logic operation that is widely used in cryptography as well as in generating parity bits for error checking and fault tolerance. XOR compares two input bits and generates one output bit. The logic is simple. If the bits are the same, the result is 0. If the bits are different, the result is 1.
Various symbols are used to designate the XOR operation including a + sign inside a circle, an underlined "V" and the caret (^). See cryptography
XOR in Cryptography
This example uses XOR and the same "secret key" to encrypt and decrypt. Although XOR logic may be used, secret key algorithms are much more sophisticated than this. See encryption algorithm