The AF9035 BDA Device driver refers to the driver for a TV tuner or digital TV receiver hardware that uses the AF9035 chipset. The chipset is typically used in USB TV tuners or PCIe cards that allow your computer to receive digital television signals (such as DVB-T, DVB-T2, or ATSC) for watching or recording TV.
"BDA" stands for Broadcast Driver Architecture, which is a Microsoft standard for TV tuner drivers on Windows. The AF9035 BDA driver is responsible for communicating with the AF9035 chipset and enabling your system to interface with and use the TV tuner device.