ASCII 85 — U

The uppercase letter U (ASCII code 85) is the twenty-first letter of the modern Latin alphabet, evolved from the Phoenician waw, gaining its rounded form in the Middle Ages. In English text, the letter u appears with a frequency of approximately 2.8%, ranking as the 13th most common letter. U is one of the five traditional vowels and nearly always follows Q in English, a spelling pattern faithfully inherited from Latin orthographic conventions.

The 26 uppercase Latin letters span ASCII codes 65 through 90, forming the capital letter block of the character set. Their placement exactly 32 code positions before the corresponding lowercase letters (97–122) was a deliberate engineering decision enabling case conversion through toggling a single bit. Uppercase letters are essential for proper nouns, sentence openings, acronyms, and programming constants. Early computing systems often supported only uppercase characters, making ASCII's inclusion of both cases a forward-looking design choice.

In the ASCII encoding table, Uppercase Letter U is assigned code point 85 in decimal (0x55 hexadecimal, 125 octal, 01010101 binary). The 7-bit ASCII standard, first published in 1963 by the American Standards Association, defines exactly 128 characters that remain the foundation of text encoding systems worldwide. UTF-8, the dominant encoding on the modern web, is fully backward compatible with ASCII — every ASCII character is encoded as the identical single byte in UTF-8, guaranteeing that Uppercase Letter U works reliably across all operating systems, programming languages, and internet protocols.