ISO 7064
The standard collecting a family of check-digit systems with names like MOD 97-10, and the reason a mistyped IBAN almost always gets caught before the money leaves.
ISO 7064 appeared in 1983 and was revised in 2003. It defines pure systems, where the check character comes from a single modulus, and hybrids that combine two. The names tell you how: MOD 11-2 works modulo 11 with radix 2, so it sometimes needs an X as an eleventh symbol, which is why ORCID identifiers can end in one. MOD 37-2 handles alphanumeric codes. MOD 97-10 produces two check digits and is used by IBAN, LEI and the RF creditor reference.
The point, compared with the Luhn algorithm on card numbers, is coverage. Luhn can be done in your head and catches single wrong digits, but misses 09 turning into 90, for example. The ISO 7064 systems want a computer or some patience, and in return catch every single wrong character and practically every swap of two adjacent ones.