From QB64.org wiki
A question mark can be used as a substitute shortcut to typing PRINT when creating code.
Usage: ?"Hello world"
Result: PRINT "Hello world"
- When the IDE cursor moves to the next code line, the question mark is changed to PRINT and the quoted text or variable is spaced appropriately.
- When an INPUT or LINE INPUT statement has no text, a question mark will appear before the input.
- A semicolon after the INPUT or LINE INPUT prompt text will add a question mark after the statement.