A position on defense commonly in the defensive backfield. The strong safety plays in the middle of the field on the strong side of the formation, closer to the line of scrimmage than the free safety. The strong safety is more involved in stopping the run and guarding the tight end on passing plays. The strong safety tends to be the larger of the two safeties, and he must be a sure tackler with solid cover skills.
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.
the ninth digit is the check digit it is calculated using an algorithm the check digit is used to validate the 8 digit bank routing number you can verify the authenticity of a check digit by running the algorithm yourself and comparing the check digit you calculate with the one that is printed on the check