The terms ABA number and routing number are frequently used interchangeably in the United States banking system, as they both refer to the nine-digit numeric code established by the American Bankers Association (ABA) to identify specific financial institutions during check clearing and electronic fund transfers. Technically, while all ABA routing numbers were originally created under the ABA routing symbol system, modern electronic banking includes electronic routing transit numbers that serve the exact same identification function. There is no practical operational difference for consumers, as both terms designate the nine-digit code located at the bottom left of a check or used in online banking forms to route funds correctly between banks.