Parity is a mathematical term that defines a value even or odd. For example, this number 4 is actually an even parity, while number 5 is an odd parity. When even and odd values are compared, such as 4 and 5, they are considered different parity. If two even or odd values are compared together, then in that case the same parity will be found.
In the study of computer science , parity is often used for tasks such as error checking. For example, a parity bit is added to the data of a block to ensure that the data has either even parity or odd parity. This type of error detection is used by many data transmission protocols, to ensure that the data is not corrupted during the transfer process.
If the protocol is set to an odd parity, all the packets received should have odd parity. Whereas if they are set to even parity, then all packets should have even parity. Otherwise, a data transmission error may occur and corresponding packet (s) may have to be resent again.
Parity is also used in a type of computer memory, which is called parity RAM . This type of RAM stores a parity bit in which each byte’s data is used to validate the integrity of each byte. Therefore, 9 bits of data is required to store each byte in RAM.
While most of the parity RAM was used in old computers, nowadays memory has started to be more reliable and that is why most systems now only use non-parity RAM. High-end workstations and servers that require consistent data integrity typically use ECC RAM, which provides a more advanced way of error checking than standard parity RAM.