use  Hex value    Character represented
\a      07      Alert (Beep, Bell) (added in C89)[1]
\b      08      Backspace
\e      1B      Escape character
\f      0C      Formfeed Page Break
\n      0A      Newline (Line Feed); see notes below
\r      0D      Carriage Return
\t      09      Horizontal Tab
\v      0B      Vertical Tab
\\      5C      Backslash
\'      27      Apostrophe or single quotation mark
\"      22      Double quotation mark
\?      3F      Question mark (used to avoid trigraphs)
