Backslash Symbol

Backslash Symbol uses the character \ (U+005C REVERSE SOLIDUS). It is the ASCII backslash used in Windows-style file paths, escape sequences, regular expressions, and several technical notations. The page covers this exact character; the forward slash /, mathematical set minus ∖, and fullwidth reverse solidus ＼ are separate Unicode values with different uses. Common examples include C:\Users\Name for a file path, \n for a newline escape sequence, A \ B for set difference in conventions that use the ASCII backslash, and \d+ in a regular expression. Each example depends on its language or notation. A backslash in source code does not automatically have the same function in prose, mathematics, a command shell, or a data format, so the surrounding syntax must be preserved. The most important editing mistake is silently replacing \ with /. That change can break a path, an escape sequence, or a pattern even though both characters are diagonal strokes. Editors should also distinguish \ from ∖ and ＼, keep the character as selectable text, and provide a readable label when it appears in an interface control or diagram. Font differences may change the angle or length of the stroke, but they do not change the encoded value U+005C. For HTML, the backslash may be written literally in UTF-8, as \, or as \. CSS source can represent it with the escape 5C when an escape is required by the surrounding syntax. In Microsoft Word, typing 005C followed by Alt+X produces \. ChromeOS Unicode input can use Ctrl+Shift+U, 5c, and Enter. In other applications, copying the character from this page is reliable as long as the pasted value is checked. Formatting follows the rules of the destination language. Keep a Windows path such as C:\Users\Name intact, preserve both characters in an escape such as \n, and do not add spaces inside a regular-expression token unless the pattern requires them. The cited Unicode, HTML, accessibility, and mathematical-notation references support the encoded identity and the distinctions used on this page. They do not make the backslash interchangeable with every diagonal mark.