09AZaz09

09AZaz09 is an alphanumeric string frequently used in computing as a canonical example of a mixed-case, digit-including sequence. It does not denote a specific real-world object; rather it serves as a placeholder or sample value in documentation and tutorials.

Composition and interpretation: The string is eight characters long and comprises digits (0,9), uppercase letters (A,Z), and lowercase letters (a,z). It demonstrates case sensitivity; 09AZaz09 is distinct from 09azAZ09 in systems that distinguish case. It can be used to test input validation, password policies, string sorting, and encoding.

Applications: In software development, 09AZaz09 appears in examples of password fields, usernames, or identifiers in sample databases, demonstration data, and form validation rules. It is also handy in teaching about regular expressions and validation logic, e.g., requiring at least one digit, one uppercase, and one lowercase character.

Related concepts: Other similar sample strings include Abc12345 or 1a2B3c4D, which vary in length or composition. The string illustrates how different systems treat case sensitivity, locale, and normalization.