Definition

Noun A set or category of symbols that includes letters of the alphabet (both uppercase and lowercase), numerical digits (0-9), and sometimes includes punctuation marks. The term specifically refers to the collective group of these characters used in writing systems and data processing.

Usage

The term "alphanumeric characters" is used to describe the permissible set of symbols for inputs in computing, data entry, and security (like passwords), or to classify text data. It emphasizes the inclusion of both letters and numbers, distinguishing it from sets containing only letters (alphabetic) or only numbers (numeric).

Examples

• The system requires a password that must contain at least one uppercase letter, one lowercase letter, and one digit from the standard alphanumeric characters.
• When filling out the form online, you can only use alphanumeric characters in the username field; special symbols are not allowed.
• The data field was defined to accept only alphanumeric characters, so the entry "Room202" is valid, but "Room#202" is rejected.

Advanced Usage

• Alphanumeric Sort/Order: A sorting method where strings are ordered based on the values of their alphanumeric characters, often following a sequence like numbers first (0-9), then letters (A-Z, a-z). For example, in an alphanumeric sort, "File10" would come after "File2".
• Alphanumeric Display/Keyboard: Refers to a device or screen section capable of showing or inputting letters and numbers, as opposed to a specialized numeric keypad or graphical display.

Variants and Related Words

• Alphanumeric (Adjective): Describing something that consists of or uses both letters and numbers.
  • Example: The product code is an alphanumeric string.
• Non-alphanumeric characters (Noun Phrase): Characters that are neither letters nor digits, such as punctuation marks (, , ), symbols, and whitespace.
• Alphabetic characters (Noun Phrase): A set containing only letters (A-Z, a-z).
• Numeric characters (Noun Phrase): A set containing only digits (0-9).

Synonyms

• Alphanumerics (Noun)
• Letters and numbers
• Alphanumeric set

Related Phrases

• Alphanumeric data: Information encoded or represented using letters and digits.
• Alphanumeric code: A series of letters and numbers used as an identifier, such as a serial number or a postal code.

Noun

1. a character set that includes letters and digits and punctuation