There are many different numbering schemes for assigning nominal numbers to entities. These generally require an agreed set of rules, or a central coordinator. The schemes can be considered to be examples of a

primary key In the relational model of databases, a primary key is a designated attribute (column) that can reliably identify and distinguish between each individual record in a table. The database creator can choose an existing unique attribute or combinati ...

of a

database management system In computing, a database is an organized collection of data or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and an ...

table Table may refer to: * Table (database), how the table data arrangement is used within the databases * Table (furniture), a piece of furniture with a flat surface and one or more legs * Table (information), a data arrangement with rows and column ...

, whose table definitions require a

database design Database design is the organization of data according to a database model. The designer determines what data must be stored and how the data elements interrelate. With this information, they can begin to fit the data to the database model.Teorey, T ...

. In

computability theory Computability theory, also known as recursion theory, is a branch of mathematical logic, computer science, and the theory of computation that originated in the 1930s with the study of computable functions and Turing degrees. The field has since ex ...

, the simplest

numbering There are many different numbering schemes for assigning nominal numbers to entities. These generally require an agreed set of rules, or a central coordinator. The schemes can be considered to be examples of a primary key In the relational model ...

scheme is the assignment of

natural number In mathematics, the natural numbers are the numbers 0, 1, 2, 3, and so on, possibly excluding 0. Some start counting with 0, defining the natural numbers as the non-negative integers , while others start with 1, defining them as the positive in ...

s to a

set Set, The Set, SET or SETS may refer to: Science, technology, and mathematics Mathematics *Set (mathematics), a collection of elements *Category of sets, the category whose objects and morphisms are sets and total functions, respectively Electro ...

of objects such as

function Function or functionality may refer to: Computing * Function key, a type of key on computer keyboards * Function model, a structured representation of processes in a system * Function object or functor or functionoid, a concept of object-orie ...

rational number In mathematics, a rational number is a number that can be expressed as the quotient or fraction of two integers, a numerator and a non-zero denominator . For example, is a rational number, as is every integer (for example, The set of all ...

graph Graph may refer to: Mathematics *Graph (discrete mathematics), a structure made of vertices and edges **Graph theory, the study of such graphs and their properties *Graph (topology), a topological space resembling a graph in the sense of discret ...

s, or words in some

formal language In logic, mathematics, computer science, and linguistics, a formal language is a set of strings whose symbols are taken from a set called "alphabet". The alphabet of a formal language consists of symbols that concatenate into strings (also c ...

. A numbering can be used to transfer the idea of computability and related concepts, which are originally defined on the natural numbers using

computable function Computable functions are the basic objects of study in computability theory. Informally, a function is ''computable'' if there is an algorithm that computes the value of the function for every value of its argument. Because of the lack of a precis ...

s, to these different types of objects. A simple extension is to assign

cardinal number In mathematics, a cardinal number, or cardinal for short, is what is commonly called the number of elements of a set. In the case of a finite set, its cardinal number, or cardinality is therefore a natural number. For dealing with the cas ...

s to physical objects according to the choice of some base of reference and of

measurement Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events. In other words, measurement is a process of determining how large or small a physical quantity is as compared to ...

units for counting or measuring these objects within a given precision. In such case, numbering is a kind of

classification Classification is the activity of assigning objects to some pre-existing classes or categories. This is distinct from the task of establishing the classes themselves (for example through cluster analysis). Examples include diagnostic tests, identif ...

, i.e. assigning a numeric property to each object of the set to subdivide this set into related subsets forming a partition of the initial set, possibly infinite and not enumeratable using a single natural number for each class of the partition. In some cases (such as computing, time-telling, and in some countries the numbering of floors in buildings)

zero-based numbering Zero-based numbering is a way of numbering in which the initial element of a sequence is assigned the index 0, rather than the index 1 as is typical in everyday non-mathematical or non-programming circumstances. Under zero-based number ...

is used, where the first entity is assigned "zero" instead of "one". Other numbering schemes are listed by field below.

Chemistry

* CAS Registry Numbers for chemical compounds * EC numbers for identifying

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

s *

UN number A UN number (United Nations number) is a four-digit number that identifies hazardous materials, and articles (such as explosives, flammable liquids, oxidizers, toxic liquids, etc.) in the framework of international trade and transport. Some h ...

s for (classes of) hazardous substances *

E number E numbers, short for Europe numbers, are codes for substances used as food additives, including those found naturally in many foods, such as vitamin C, for use within the European Union (EU) and European Free Trade Association (EFTA). Commonly ...

s for

food additive Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives, such as vinegar ( pickling), salt ( salting), smoke ( smoking) and sugar ( crystallization), have been used f ...

Communications

*The

E.164 E.164 is an international standard (ITU-T Recommendation), titled ''The international public telecommunication numbering plan'', that defines a numbering plan for the worldwide public switched telephone network (PSTN) and some other data netw ...

numbering plan for

telephone A telephone, colloquially referred to as a phone, is a telecommunications device that enables two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most ...

numbers, including: **

Country calling code Telephone country codes are telephone number prefixes for reaching subscribers in foreign countries or areas by international direct dialing (IDD). Country codes are defined by the International Telecommunication Union (ITU) in ITU-T standards ...

s **

North American Numbering Plan The North American Numbering Plan (NANP) is an integrated telephone numbering plan for twenty-five regions in twenty countries, primarily in North America and the Caribbean. This group is historically known as World Zone 1, World Numbering Zone ...

** Numbering plans by country ***Argentina:

Argentine telephone numbering plan Argentines, Argentinians or Argentineans are people from Argentina. This connection may be residential, legal, historical, or cultural. For most Argentines, several (or all) of these connections exist and are collectively the source of their ...

***Australia:

Australian telephone numbering plan Telephone numbers in Australia are defined and administered by the Australian Communications and Media Authority (ACMA) under delegation by the Department of Infrastructure, Transport, Regional Development, Communications and the Arts, persuant ...

***China:

China telephone numbering plan Telephone numbers in the People's Republic of China are administered according to the Telecommunications Network Numbering Plan of China. The structure of telephone numbers for landlines and mobile service is different. Landline telephone number ...

***France:

French telephone numbering plan The French telephone numbering plan is used in Metropolitan France, French overseas departments and some overseas collectivities. Since 1996, Metropolitan France uses a ten-digit closed numbering plan, where the first two digits denote a geogra ...

***Hong Kong:

Hong Kong telephone numbering plan Hong may refer to: Places *Høng, a town in Denmark *Hong Kong, a city and a special administrative region in China *Hong, Nigeria *Hong River in China and Vietnam *Lake Hong in China Surnames *Hong (Chinese surname) *Hong (Korean surname) O ...

***India: India telephone numbering plan ***Japan: Japanese telephone numbering plan ***Singapore:

Singapore telephone numbering plan Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree o ...

***United Kingdom: UK telephone numbering plan ***Germany: German telephone numbering plan *The

IP address An Internet Protocol address (IP address) is a numerical label such as that is assigned to a device connected to a computer network that uses the Internet Protocol for communication. IP addresses serve two main functions: network interface i ...

allocation scheme (

IANA The Internet Assigned Numbers Authority (IANA) is a standards organization that oversees global IP address allocation, autonomous system number allocation, root zone management in the Domain Name System (DNS), media types, and other Internet P ...

) *The DNIC prefixes of

X.25 X.25 is an ITU-T standard protocol suite for Packet switched network, packet-switched data communication in wide area network, wide area networks (WAN). It was originally defined by the CCITT, International Telegraph and Telephone Consultative Co ...

NUAs (Network User Address) assigned by the

ITU The International Telecommunication Union (ITU)In the other common languages of the ITU: * * is a specialized agency of the United Nations responsible for many matters related to information and communication technologies. It was established ...

Object identifier In computing, object identifiers or OIDs are an identifier mechanism standardized by the International Telecommunication Union (ITU) and ISO/IEC for naming any object, concept, or "thing" with a globally unambiguous persistent name. Syntax and lex ...

s (OID)

Computing

Line number In computing, a line number is a method used to specify a particular sequence of characters in a text file. The most common method of assigning numbers to lines is to assign every line a unique number, starting at 1 for the first line, and increm ...

Products

* The GS1 numbering scheme, including ** GTIN for products, which includes the UPC and

EAN-13 International Article Number, also known as European Article Number (EAN), is a global standard that defines a barcode format and a unique numbering system used in retail and trade. It helps identify specific types of retail products based on thei ...

barcode A barcode or bar code is a method of representing data in a visual, Machine-readable data, machine-readable form. Initially, barcodes represented data by varying the widths, spacings and sizes of parallel lines. These barcodes, now commonly ref ...

s **

ISBN The International Standard Book Number (ISBN) is a numeric commercial book identifier that is intended to be unique. Publishers purchase or receive ISBNs from an affiliate of the International ISBN Agency. A different ISBN is assigned to e ...

codes for books **

ISSN An International Standard Serial Number (ISSN) is an eight-digit to uniquely identify a periodical publication (periodical), such as a magazine. The ISSN is especially helpful in distinguishing between serials with the same title. ISSNs a ...

codes for periodicals *

Vehicle identification number A vehicle identification number (VIN; also called a chassis number or frame number) is a unique code, including a serial number, used by the automotive industry to identify individual motor vehicles, towed vehicles, motorcycles, scooters a ...

Stock keeping unit In inventory management, a stock keeping unit (abbreviated as SKU, pronounced or ) is the unit of measure in which the stocks of a material are managed. It is a distinct type of item for sale, purchase, or tracking in inventory, such as a produ ...

(SKU)

People

Identification numbers

*National identification numbers ** Personal Numeric Code (Romania) **

Personal identification number (Denmark) The Danish Personal Identification number ( or informally , or ) is a national identification number, which is part of the personal information stored in the Civil Registration System (, ). The register was established in 1968 by combining inf ...

** Social Security number (United States) **

Social insurance number A social insurance number (SIN) ( (NAS)) is a number issued in Canada to administer various government programs. The SIN was created in 1964 to serve as a client account number in the administration of the Canada Pension Plan and Canada's varie ...

(Canada) ** INSEE number (France) **

National Insurance National Insurance (NI) is a fundamental component of the welfare state in the United Kingdom. It acts as a form of social security, since payment of NI contributions establishes entitlement to certain state benefits for workers and their famil ...

number (United Kingdom) **

Aadhaar Aadhaar (Hindi: आधार, ) is a twelve-digit unique identity number that can be obtained voluntarily by all residents of India, based on their biometrics and demography, demographic data. The data is collected by the Unique Identification ...

(India) *

Personal Public Service Number The Personal Public Service Number (PPS Number or simply PPSN) (, or ) is a unique identifier of individuals in Ireland, acting as a national identification number. It is issued by the Client Identity Services section of the Department of Socia ...

(Republic of Ireland) *

Tax file number A tax file number (TFN) is a unique identifier issued by the Australian Taxation Office (ATO) to each taxpaying entity—an individual, company, Pension fund, superannuation fund, partnership, or Trust law, trust. Not all individuals have a TFN, a ...

(Australia) *

Unique Master Citizen Number Unique Master Citizen Number ( sh-Latn-Cyrl, Jedinstveni matični broj građana, Јединствени матични број грађана, separator=" / ", JMBG / , , , EMŠO) is an identification number that was assigned to every citizen of ...

(former Yugoslavia) *

Det Centrale Personregister The Danish Personal Identification number ( or informally , or ) is a national identification number, which is part of the personal information stored in the Civil Registration System (, ). The register was established in 1968 by combining inf ...

(Denmark)

Ordinals for names

Regnal number Regnal numbers are ordinal numbers—often written as Roman numerals—used to distinguish among persons with the same regnal name who held the same office, notably kings, queens regnant, popes, and rarely princes and princesses. It is common t ...

s **

Princes of Reuss Reuss ( ) was the name of several historical states located in present-day Thuringia, Germany. Several lordships of the Holy Roman Empire which arose after 1300 and became Imperial Counties from 1673 and Imperial Principalities in the late 18th ...

** Popes' ordinals * Generational ordinal suffix to names

Topics

Dewey Decimal Classification The Dewey Decimal Classification (DDC) (pronounced ) colloquially known as the Dewey Decimal System, is a proprietary library classification system which allows new books to be added to a library in their appropriate location based on subject. ...

and

Universal Decimal Classification The Universal Decimal Classification (UDC) is a bibliographic and library classification representing the systematic arrangement of all branches of human knowledge organized as a coherent system in which knowledge fields are related and inter-lin ...

for books *

West American Digest System The West American Digest System is a system of identifying points of law from reported cases and organizing them by topic and key number. The system was developed by Thomson West, West Publishing to organize the entire body of Law of the United Sta ...

legal topic numbering scheme

Geography and transport

Postal code A postal code (also known locally in various English-speaking countries throughout the world as a postcode, post code, PIN or ZIP Code) is a series of letters or numerical digit, digits or both, sometimes including spaces or punctuation, inclu ...

s ** ZIP codes * Geocodes (used also as ''fine-grained postal codes''): **

Geohash Geohash is a public domain geocode system invented in 2008 by Gustavo Niemeyer * * * which encodes a geographic location into a short string of letters and digits. Similar ideas were introduced by G.M. Morton in 1966. It is a hierarchical spat ...

Open Location Code The Open Location Code (OLC) is a geocode#Systems_of_regular_grids, geocode based on a system of regular grids for identifying an area anywhere on the Earth. It was developed at Google's Zürich engineering office, and released late October 2014. ...

Global Location Number The Global Location Number (GLN) is part of the GS1 systems of standards. It is a simple tool used to identify a location and can identify locations uniquely where required. This identifier is compliant with norm ISO/IEC 6523. The GS1 Identifica ...

s by GS1 *

FIPS place code The Federal Information Processing Standards (FIPS) of the United States are a set of publicly announced standards that the National Institute of Standards and Technology (NIST) has developed for use in computer systems of non-military United States ...

s *

House numbering House numbering is the system of giving a unique number to each building in a street or area, with the intention of making it easier to locate a particular building. The house number is often part of a Address (geography), postal address. The ter ...

schemes *

Floor numbering A storey (Commonwealth English) or story (American English), is any level part of a building with a floor that could be used by people (for living, work, storage, recreation, etc.). Plurals for the word are ''storeys'' (UK, CAN) and ''storie ...

Room number A room number is a number assigned to a room within a building. Its purpose is to identify a particular room, and help building inhabitants locate that room. Room numbers may consist of three numerical digit, digits, but can be any number of digi ...

* See also:

Country code A country code is a short alphanumeric identification code for countries and dependent areas. Its primary use is in data processing and communications. Several identification systems have been developed. The term ''country code'' frequently re ...

;

Address (geography) An address is a collection of information, presented in a mostly fixed format, used to give the location of a building, apartment, or other structure or a plot of land, generally using political boundaries and street names as references, along ...

Vehicles

Vehicle registration plate A vehicle registration plate, also known as a number plate (British, Indian and Australian English), license plate (American English) or licence plate (Canadian English), is a metal or plastic plate attached to a motor vehicle or trailer for ...

s *

British Carriage and Wagon Numbering and Classification A number of different numbering and classification schemes have been used for carriages and wagons on Britain's railways, and this page explains the principal systems. Carriages and wagons (either not self-propelled, or part of a multiple unit wh ...

British Rail locomotive and multiple unit numbering and classification #REDIRECT British Rail locomotive and multiple unit numbering and classification {{R from other capitalisation ...

UIC classification of goods wagons This list contains the UIC classification of goods wagons and their meanings. The description is made up of a category letter (in capitals) and usually several index letters (in lower case). The international system for the classification of goods ...

Roads

Road numbering schemes *

Arlington County, Virginia, street-naming system This article details the street-naming system of Arlington County, Virginia in the United States. Although the streets of Arlington County are not laid out on a grid plan, its local streets follow sequential numbered or alphabetic patterns t ...

China road numbering A route (or road) number, designation or abbreviation is an identifying numeric (or alphanumeric) designation assigned by a highway authority to a particular stretch of roadway to distinguish it from other routes and, in many cases, also to indica ...

Great Britain road numbering scheme In Great Britain, there is a numbering scheme used to Categorization, classify and identify all roads. Each road is given a single letter (representing a category) and a subsequent number (between one and four digits). Though this scheme was in ...

European route The international E-road network is a numbering system for roads in Europe developed by the United Nations Economic Commission for Europe (UNECE). The network is numbered from E1 up and its roads cross national borders. It also reaches Central ...

UNECE The United Nations Economic Commission for Europe (ECE or UNECE) is an intergovernmental organization or a specialized body of the United Nations. The UNECE is one of five regional commissions under the jurisdiction of the United Nations Econ ...

Numbered highways in the United States Highways are split into at least four different types of systems in the United States: Interstate Highways, U.S. Highways, state highways, and county highways. Highways are generally organized by a route number or letter. These designations are ...

* Edmonton, Alberta#Street layout *

Montreal Montreal is the List of towns in Quebec, largest city in the Provinces and territories of Canada, province of Quebec, the List of the largest municipalities in Canada by population, second-largest in Canada, and the List of North American cit ...

* Highways in Australia#Route numbering systems

Others/general

* API well numbers for numbering

oil and gas A fossil fuel is a flammable carbon compound- or hydrocarbon-containing material formed naturally in the Earth's crust from the buried remains of prehistoric organisms (animals, plants or microplanktons), a process that occurs within geologi ...

wells in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

Bank card number A payment card number, primary account number (PAN), or simply a card number, is the card identifier found on payment cards, such as credit cards and debit cards, as well as stored-value cards, gift cards and other similar cards. In some situat ...

International Bank Account Number The International Bank Account Number (IBAN) is an internationally agreed upon system of identifying bank accounts across national borders to facilitate the communication and processing of cross border transactions with a reduced risk of transc ...

International Geo Sample Number The International Generic Sample Number or IGSN is a persistent identifier for a Sample (material), sample. As an active persistent identifier it can be resolved through the Handle System. The system is used in production by the System for Earth Sam ...

(IGSN) *

International Statistical Classification of Diseases and Related Health Problems The International Classification of Diseases (ICD) is a globally used medical classification that is used in epidemiology, health management and clinical diagnostics, diagnosis. The ICD is maintained by the World Health Organization (WHO), which ...

for

disease A disease is a particular abnormal condition that adversely affects the structure or function (biology), function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical condi ...

s *The

MAC address A MAC address (short for medium access control address or media access control address) is a unique identifier assigned to a network interface controller (NIC) for use as a network address in communications within a network segment. This use i ...

allocation scheme for hardware addresses of certain networking products *

National Animal Identification System The National Animal Identification System, (naisG) is a government-run program in the United States intended to extend government animal health surveillance by identifying and tracking specific animals. Administered at the federal level by the An ...

* National Pokédex *The NSAP allocation scheme *

Post office box A post office box (commonly abbreviated as P.O. box, or also known as a postal box) is a uniquely addressable lockable box located on the premises of a post office. In some regions, particularly in Africa, there is no door-to-door delivery ...

Production code number A production code number, also known as the production code (PC) or episode code, is an alphanumeric designation used to uniquely identify episodes within a television series. As each studio can freely generate its own PC format, it cannot be ...

Stamp numbering system Philatelists' traditional method of identifying postage stamps uniquely has long been to number each country's stamps consecutively; Norway #1 is the 4-skilling blue stamp issued in 1855, and so forth. However, this seemingly straightforward numbe ...

* Wikipedia markup syntax for numbered lists

References

{{Authority control *