The Realtek Bluetooth 4.0 Adapter Windows driver is a software driver that enables your Windows computer to communicate with Bluetooth 4.0 (and in some cases, lower versions) hardware provided by Realtek. This driver allows you to connect Bluetooth-enabled devices, such as wireless headphones, keyboards, mice, printers, and other peripherals, to your computer via Bluetooth.

Bluetooth 4.0 (often referred to as Bluetooth Low Energy, or BLE) is an energy-efficient version of Bluetooth that supports faster data transfers and lower power consumption compared to earlier Bluetooth versions. The Realtek Bluetooth 4.0 Adapter is typically integrated into many modern laptops, desktops, or as an external USB Bluetooth dongle.