The standard set of characters includes all English letters, numbers, and most punctuation.
This is every printable character that appears on the standard US keyboard.
ABCDEFGHIJKLMNPQRSTUVWXYZ
abcdefghijklmnopqrstuvwxyz
1234567890
!?.,;:'"@#$%^&*()-+\/|[]{}<>=_`~
The reduced set of characters includes uppercase English letters, numbers, and some punctuation.
ABCDEFGHIJKLMNPQRSTUVWXYZ
1234567890
!?.,;:'"@*()-+/=