What is CBC-MAC (Cipher Block Chaining Message Authentication Code)?

A cipher block chaining message authentication code (CBC-MAC) is a method for developing a message confirmation code from a block cipher. The message is encrypted with some block cipher algorithm in CBC mode to make a chain of blocks. Then each block depends on the encryption of the previous block and guarantees that a change to any of the plaintext bits will make the last encrypted block to change in a manner that cannot be anticipated without knowing the key to the block cipher.