A jiàoyàn mǎ (checksum) is a small piece of data used to verify the integrity of a larger set of information during transmission or storage. The term combines three characters: xiào (to check or verify), yàn (to test or examine), and mǎ (code or symbol). Together, they literally mean 'verification code' — emphasizing its function as a computational safeguard against errors like data corruption or transmission glitches.

This term appears frequently in computing, telecommunications, banking, and logistics systems — for instance, in QR codes, ID numbers, credit card numbers, or file downloads. It is not used in everyday conversation but belongs to technical and professional registers. While laypeople may encounter checksums without knowing the term (e.g., when a payment app displays a 'verification code'), the word itself is domain-specific and rarely appears outside contexts involving digital data validation.