ASCII characters occupy the low order 8 bits of 16-bit Unicode:


0 9 start at hex 30, through hex 39

A O start at hex 41, through hex 4F

P Z start at hex 50, through hex 5A

a o start at hex 61, through hex 6F

p- z start at hex 70, through hex 7a

a space or blank is hex 20

a period is hex 2E and a comma is hex 2C


System.out.print prints a question mark ( ? ) for any unrecognizable Unicode characters.