First question mark

A symbol that is thought to be the world's earliest question mark has been identified by a Cambridge academic. The symbol is two dots, one above the other, similar in appearance to a colon, rather than the familiar squiggle of the modern question mark. The double-dot symbol appears in Syriac manuscripts of the Bible dating back to the fifth century. The double-dot mark, known to later grammarians as zawga elaya, is written above a word near the start of a sentence to tell the reader that it is a question. It doesn't appear on all questions: ones with a wh- word don't need it, just as in English 'Who is it' can only be a question (although we use a question mark anyway). But a question like 'You're going away?' needs the question mark to be understood; and in Syriac, zawga elaya marks just these otherwise ambiguous expressions. Source: http://www.cam.ac.uk/research/news/the-riddle-of-the-syriac-double-dot-it%E2%80%99s-the-world%E2%80%99s-earliest-question-mark/