An identifier is a unique name or label assigned to a programming element such as a variable, function, or class, to differentiate it from other elements within a program’s scope. Identifiers are essential for programmers to reference and manipulate the values or objects associated with them. The syntax and rules for creating identifiers may vary across programming languages, but generally, they consist of alphanumeric characters and underscores, and cannot begin with a number.


The phonetic pronunciation of the keyword “Identifier” is: /aɪˈdɛntɪfaɪər/ or in IPA symbols: [aɪ’dɛntɪfaɪər].

Key Takeaways

  1. An identifier is a unique name assigned to a programming element, such as a variable, function, or class, to distinguish it from other elements.
  2. Identifiers must follow specific rules defined by the programming language, including rules about the first character, allowed characters, and case sensitivity.
  3. Using clear, descriptive names for identifiers helps make the code more readable and understandable for both you and others working on the project.


The technology term “Identifier” is important because it serves as a unique label or name assigned to various elements within a programming language, database, or system, allowing for easy distinction and reference.

Identifiers play a crucial role in software development, data organization, and communication between systems.

They enable developers to write clear and maintainable code by giving meaningful names to variables, functions, classes, and other programming constructs.

Furthermore, identifiers act as a fundamental building block in databases, ensuring data integrity and efficient retrieval of information.

Overall, the concept of identifiers is essential in delivering organized, efficient, and reliable technology solutions.


An identifier is a crucial element in the realm of computer programming and data organization, as it serves the purpose of naming and distinguishing various entities within a program or database. Consisting of a sequence of characters, often letters, numbers, or special symbols, identifiers are assigned to variables, classes, functions, and other essential elements to create ease of reference when executing complex programming tasks.

By establishing a logical naming convention, identifiers enhance the clarity and structure of the code, making it easier for fellow developers to understand, maintain, and troubleshoot. Apart from improving code readability, identifiers also play an essential role in memory allocation and data manipulation.

When an identifier is assigned to a variable, the memory location in which the data is stored is also linked, allowing the developer a more efficient way to access and manipulate the stored data without needing to recall specific memory locations. Moreover, identifiers ensure that distinct entities within the code can operate independently and do not conflict with each other, contributing indispensably to the accurate execution of the program’s intended functionality.

Thus, the careful selection and assignment of identifiers is vital for designing structured, maintainable, and efficient software applications.

Examples of Identifier

Universal Product Code (UPC): The UPC is a common identifier used in commerce, especially in retail. This technology provides a unique numerical identifier and corresponding barcode to each product, which can be scanned at point-of-sale during purchase. It streamlines inventory management, pricing, and tracking for retailers and suppliers.

Radio-frequency identification (RFID): RFID technology uses radio waves to identify and track objects uniquely. RFID tags, embedded with microchips, store information about objects and can transmit this data to RFID readers, even from a distance. They are widely used in supply chain management, logistics, warehouse management, and security systems.

International Mobile Equipment Identity (IMEI): The IMEI is a unique 15-digit identifier assigned to every mobile device globally, such as smartphones and tablets. The identifier can be used to trace, track, and control stolen or lost devices, ensuring the safety of user data and preventing unauthorized use. It also helps in preventing device cloning, improving network security, and assisting with device warranty and repair services.

Identifier FAQ

What is an identifier?

An identifier is a sequence of characters that represents a variable, function, or other named entities in a programming language. Identifiers are used to give names to various program elements, making the code more readable and maintainable.

What are the rules for naming identifiers?

While rules for naming identifiers vary by programming language, there are common guidelines to follow. Generally, identifiers must start with a letter (a-z or A-Z) or an underscore (_), followed by any combination of letters, digits (0-9), or underscores. Identifiers cannot start with a number and should not include special characters or spaces.

Are identifiers case-sensitive?

In most programming languages, identifiers are case-sensitive, meaning that “myVariable” and “MyVariable” would be treated as distinct identifiers. However, some languages, like Visual Basic, are case-insensitive, treating them as the same identifier.

What are some examples of reserved words that cannot be used as identifiers?

Reserved words are keywords that have predefined meanings in a programming language and cannot be used as identifiers. Examples include “if”, “else”, “while”, “for”, “class”, and “import”. The specific list of reserved words depends on the programming language in use.

What is the difference between an identifier and a variable?

An identifier is the name given to a program element, such as a variable, function, or class. A variable, on the other hand, is a specific type of identifier used to store data in a program. In other words, an identifier is a broader term encompassing all named elements, whereas a variable is a specific type of named element that holds a value.

Related Technology Terms

  • Unique Identifier
  • Global Identifier
  • Local Identifier
  • Object Identifier
  • Resource Identifier

Sources for More Information


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