[1][2] This "extra" LRC word at the end of a block of data is very similar to checksum and cyclic redundancy check (CRC).
While simple longitudinal parity can only detect errors, it can be combined with additional error-control coding, such as a transverse redundancy check (TRC), to correct errors.
The transverse redundancy check is stored on a dedicated "parity track".
[4][5][6] International standard ISO 1155[7] states that a longitudinal redundancy check for a sequence of bytes may be computed in software by the following algorithm: which can be expressed as "the 8-bit two's-complement value of the sum of all bytes modulo 28" (x AND 0xFF is equivalent to x MOD 28).
An 8-bit LRC such as this is equivalent to a cyclic redundancy check using the polynomial x8 + 1, but the independence of the bit streams is less clear when looked at in that way.