Error Notes
The Federal Reserve has stringent policies in place to produce perfect notes. Printing currency is a highly complex process though and some error notes do escape to the general public.
The seal and serial number is missing only from the right side.
The reverse printing is missing.
Partial portion of the back is seen on the front.
The paper was folded prior to printing. This creates a gutter effect on the note.
The paper was folded prior to printing.
The back is faintly seen on the front.
The second printing is misaligned.
The rear is missing ink.
Article mentioning all errors of this type.