Parity

ParityA very basic method of error checking that checks data for errors during a transmission or on a data storage mechanism. Parity works by setting a parity bit to an even or odd number. For example, if the binary stream contains an even amount of 1's and the parity bit is odd, the computer would generate a parity error because the data is corrupt. In the picture to the right, is an example of an 8-bit binary number with a ninth parity bit and examples of odd and even parity binary with their associated parity bit.

In the past most memory manufacturers had the option between parity and non-parity memory. However, today's computer memory is more reliable and because of costs parity error checking is no longer used. When a memory error does occur with a computer that has no-parity memory it can cause the computer to freeze or generate an error.

Tip Parity error checking only detects and reports errors, it will not correct the errors found.

Also see: BERT, CRC, ECC, Error control, Mark parity, Memory definitions, No-parity, Parity bit, Parity Check, Serial, Space parity