Modern checks use various physical and chemical safeguards to deter alteration or duplication: Breaking Down the Parts of a Check | Wintrust
: Located in the bottom-right; the check is only valid once signed by the account holder. Technical & Coded Information bank check
: A series of numbers at the bottom printed in magnetic ink: Routing Number : A nine-digit code identifying your bank. Account Number : Identifies your specific checking account. Modern checks use various physical and chemical safeguards