Paritätsfunktion

Paritätsfunktion is a term used in computer science and information theory. It refers to a function that determines the parity of a binary number. Parity refers to whether the number of '1's in a binary representation is even or odd. The paritätsfunktion typically outputs a single bit: 0 for even parity and 1 for odd parity.

There are two common types of paritätsfunktion: even parity and odd parity. An even parity function returns 0 if the number of set bits (1s) is even, and 1 if the number of set bits is odd. Conversely, an odd parity function returns 1 if the number of set bits is even, and 0 if the number of set bits is odd. The XOR (exclusive OR) operation is fundamental to calculating parity. For a sequence of bits, the XOR sum of all bits yields the parity bit.

Paritätsfunktionen are primarily used for error detection in digital communication and data storage. By appending a parity bit to a block of data, it's possible to detect single-bit errors. If a single bit flips during transmission or storage, the parity of the received data will change, indicating an error. While simple and effective for detecting single errors, parity checks cannot detect errors where an even number of bits are flipped, nor can they correct errors. More sophisticated error correction codes are used for greater reliability.