Final answer:
In ASCII, a single parity bit is added to the character string at the end to help detect errors in data transmission or storage.
Step-by-step explanation:
In the American Standard Code for Information Interchange (ASCII), a single parity bit is added to the character string at the end. The purpose of this parity bit is to help detect errors in the transmission or storage of data. It is used to ensure that the number of ones in the character string is always even or odd, depending on the parity scheme being used.