The Fastboot Interface (Google USB ID) driver is a special driver used by Android devices for a mode called Fastboot. Fastboot is a protocol used primarily for flashing Android devices (like installing custom firmware, recovery images, or updating the bootloader) from a computer to the device while the device is in Fastboot mode (also known as Bootloader mode).

In Fastboot mode, the device can communicate with your computer through a USB connection, allowing low-level operations like unlocking the bootloader, flashing recovery images, or modifying the system partitions. The Google USB ID specifically identifies the device when connected to a computer in Fastboot mode.