Question mark
In the early 13th century, when the growth of communities of scholars (universities) in Paris and other major cities led to an expansion and streamlining of the book-production trade, punctuation was rationalized by assigning Alcuin's stroke-over-dot specifically to interrogatives; by this time the stroke was more sharply curved and can easily be recognized as the modern question mark.
Chess annotation symbols
The double question mark "??" indicates a blunder, a very bad mistake. Typical moves which receive double question marks are those that overlook a tactic that wins substantial material or overlook a checkmate. A "??"-worthy move usually results in an immediately lost position. Occasionally, the sign is used for a move which transforms a won position into a draw, perhaps because the annotator feels that the mistake is unworthy of the player's skill level. They occur at all levels of play to all human competitors.