0123456789ab

0123456789ab is a 12-character alphanumeric string that begins with the ten decimal digits 0 through 9 and ends with the letters a and b in lowercase. In its form, it uses a subset of hexadecimal digits, since hex digits range from 0–9 and a–f, but this sequence only includes a and b among the alphabetic hex digits.

As a simple, deterministic sequence, the string is often used in computing contexts as a sample input for testing and demonstration. It can serve in exercises that require basic string processing, such as measuring length, extracting substrings, or verifying lexicographic ordering. It is also commonly used as a placeholder token in documentation or example data where a compact alphanumeric value is desired.

If interpreted as a hexadecimal number, 0123456789ab is a valid hex literal (leading zeros do not affect value) and would correspond to a non-negative integer. However, because it omits the digits c through f, it represents only a partial range of the hexadecimal numeral system and is not typically treated as a complete hex representation.

In summary, 0123456789ab is mainly of interest as a concise, predictable example string used for testing, illustration, and placeholder purposes in software development and technical writing. See also hexadecimal numeral system, alphanumeric strings, and test vectors.