The Advanced Encryption Standard (AES) is a specification for the encryption of electronic data established by the U.S National Institute of Standards and Technology (NIST) in 2001. It is included in the ISO/IEC 18033-3 standard.
AES is a symmetric-key algorithm, meaning the same key is used for both encrypting and decrypting sensitive data.
The AES XTS is a XEX-based tweaked-codebook mode with ciphertext stealing. This mode of operation is mainly used to encrypt sector-addressable data at rest. Thus it has to be compliant with SATAI, SATAII and/or SATAIII specifications to be used. It uniquely encrypts each sector by encrypting the sector's ID additionally to the data. Therefore, two identical data blocks in different sectors won't share the same encryption.