DTMF tones (Dual-Tone Multi-Frequency tones) are the sounds generated when someone presses keys on a telephone keypad, with each number producing a unique combination of two simultaneous audio frequencies. These tones enable interactive communication between callers and automated phone systems, allowing customers to navigate menus, enter account numbers, and input payment card details. Each digit (0-9) plus symbols (* and #) produces a distinct frequency pair that systems can recognize and interpret. In secure payment contexts, DTMF tones are the underlying technology that enables customers to enter sensitive information via their phone keypad, which can then be masked or suppressed to prevent recording or interception while still being processed for payment authorization.
See also:
