The Logitech Driver Interface (LDI) is a generic term used to refer to the software interface that allows Logitech devices, such as gaming peripherals (mice, keyboards, steering wheels, etc.), to communicate with Windows computers. This interface typically includes the necessary drivers and utilities for Logitech hardware to function properly. For example, when you install Logitech software or drivers, the Logitech Driver Interface ensures that the devices are correctly recognized by Windows and operate as intended.
In the context of devices like the Logitech Driving Force Pro (steering wheel), the Logitech Driver Interface would be the underlying driver software that facilitates communication between the steering wheel and the PC, enabling features like force feedback, button mappings, and other configurations.