ASCII 33 — !

The exclamation mark expresses emphasis, surprise, commands, or excitement in written text. In programming, it takes on critical logical meaning — in C, JavaScript, and many other languages, '!' is the logical NOT operator that inverts boolean values. The '!=' operator means 'not equal' across dozens of languages. In Unix shells, '!' triggers history expansion (bang commands), and in languages like Rust it indicates macro invocations. In mathematics, 'n!' denotes the factorial function, computing the product of all positive integers up to n.

Punctuation marks serve as the structural scaffolding of written language, delineating sentences, clauses, and phrases while conveying emphasis and grouping. In programming, these same characters gain powerful additional roles as operators, statement terminators, delimiters, and syntactic markers that compilers and interpreters rely upon. This dual significance in both natural language and code syntax means punctuation characters carry outsized functional importance relative to their small count in the ASCII character set.

In the ASCII encoding table, Exclamation Mark is assigned code point 33 in decimal (0x21 hexadecimal, 041 octal, 00100001 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 Exclamation Mark works reliably across all operating systems, programming languages, and internet protocols.