serial number
engine number – identification number marked on an engine
English numerals – Name of numbers in English
Numbering scheme – System of rules for assigning mathematical values to database items
Part number – Identifier of a particular part design in engineering
Product key – Specific software-based key for a computer program
Sequence number – Mathematical concept
SQL – Programming language for management and use of relational databases (serial identifiers for databases)
United Kingdom military aircraft registration number – Identification for United Kingdom military aircraft
United States military aircraft serial numbers – system for identifying an airport
Vehicle identification number – System for identifying vehicles
Arithmometer – 19th-century mechanical calculator patented by French inventor Thomas de Colmar – one of the first machines to sport a unique serial number