escapesyntax

Escape syntax refers to the notation used to represent characters that have special meaning in a programming language, data format, or text-processing system. It relies on an escape character followed by a code or sequence that yields a literal character or a value otherwise not expressible in the ordinary syntax. The primary purpose is to allow inclusion of characters that would otherwise terminate a string, alter parsing, or be nonprintable.

Common forms include backslash escapes such as \n for a newline, \t for a tab, and \\ for a literal backslash. Many languages also support hexadecimal or octal escapes like \x7F or \077, and Unicode escapes such as \u00A9 or \U0001F600. Some formats, notably JSON, specify a fixed set of escapes and require the use of the escape character for non-alphanumeric characters.

Escape syntax also appears in regular expressions, where metacharacters are escaped with a backslash to lose their special meaning, for example \. or \d. In shell scripting, backslashes prevent interpretation of the following character, and many languages offer raw or verbatim string forms that suppress escapes.

Security and portability concerns arise because improper escaping can enable injection vulnerabilities or break tooling across languages and versions. Good practices include context-aware escaping, validation of input, and using language-provided escaping utilities.