touchback - (American football) a play in which the opposing team has kicked the football into your end zone.
From Wikipedia, the free encyclopedia. A check digit is a form of redundancy check used for error detection on identification numbers, such as bank account numbers, which are used in an application where they will at least sometimes be input manually. It is analogous to a binary parity bit used to check for errors in computer-generated data.
Your routing number will always be 9 digits and begin with a 0, 1, 2 or 3. Look in the bottom left corner of your check (not the deposit slip). When you enter your routing number, just enter the 9 digits; no spaces, punctuation or other characters that appear before the 9-digit number. If your check displays an ACH number (this is uncommon), use that instead of the routing number.