ASCII 123 — {

The left curly brace is a foundational syntactic element in C-family programming languages, marking the beginning of code blocks for functions, loops, conditionals, classes, and namespaces. In JSON, '{' begins an object literal. In CSS, it opens a selector's declaration block. In regular expressions, '{n,m}' specifies quantifier repetition ranges. The placement of opening braces — same line (K&R style) versus next line (Allman style) — is the subject of one of programming's most enduring and emotionally charged code formatting debates across developer communities.

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, Left Curly Brace is assigned code point 123 in decimal (0x7B hexadecimal, 173 octal, 01111011 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 Left Curly Brace works reliably across all operating systems, programming languages, and internet protocols.