Question mark (punctuation)

Forms and typographic varieties

The familiar upright question mark is the most common form, but there are typographic and regional differences. In Spanish an inverted question mark (¿) is placed at the beginning of an interrogative sentence to signal the question from the outset; see Spanish punctuation. In some languages and older typefaces the mark may appear with a longer or more curved stroke. There is also a combined interrogation–exclamation mark known as the interrobang (‽), introduced in the 20th century as a single glyph to express surprise or disbelief alongside a question; readers can find histories of typographic inventions at type history.

History and origin

The question mark's origins are traced to medieval manuscript shorthand. One widely cited theory points to the Latin word quaestio ("question"), abbreviated in manuscripts as the letters Q and o; the Q was later written above the o and gradually stylized into the curving mark and dot that form the modern glyph. Other manuscript practices produced a slanted curved mark with a point beneath it during the Middle Ages. For surveys of historical sources and paleographic evidence, consult Latin script studies and medieval punctuation research.

Usage, spacing and style

Style guides differ about spacing and repetition. In English and many languages the question mark directly follows the last word without a space; exceptions exist in French and some typographic traditions where a thin or nonbreaking space precedes certain punctuation marks, including the question mark. See comparisons of typographic spacing at spacing conventions. Writers sometimes use multiple question marks for emphasis in informal writing ("Really???"); such usage is typically avoided in formal prose.

In computing, programming and encoding

The question mark has roles beyond punctuation. In many programming languages it appears in operators (for example, the ternary conditional operator in languages like C, Java and JavaScript often uses ? and : together). It is also a special character in pattern matching and regular expressions where it denotes optionality or quantification. In character encoding the upright question mark corresponds to ASCII code 63 and Unicode U+003F; the inverted question mark is U+00BF. For technical references see computing references at programming symbols and Unicode charts.

Notable facts and distinctions

• The inverted question mark (¿) used in Spanish appears at the start of interrogative sentences to show that a question begins; the closing mark is the ordinary question mark.
• The interrobang (‽) was proposed as a single glyph to combine question and exclamation; it remains a niche symbol but is encoded in Unicode. More on punctuational variants is available at punctuation variants.
• Question marks are part of everyday digital communication, including emoticons and emojis, where they can express confusion, inquiry or emphasis.

Across languages and contexts, the question mark remains a concise visual cue that a sentence asks something. Its simple shape and long history make it one of the most recognizable pieces of punctuation in modern writing systems.