The kilobyte is a multiple of the unit byte for digital information. The International System of Units (SI) defines the prefix kilo as 1000 (10³); therefore one kilobyte is 1000 bytes. The unit symbol for the kilobyte is kB. In some fields of information technology kilobyte has traditionally also been used to denote 1024 (2¹⁰) bytes, which arises from binary exponentiation common to digital circuitry. In this context the unit symbol K or KB has been common.