Which component is essential for interfacing between hardware and software in a computer system?

The device driver is essential for interfacing between hardware and software in a computer system because it acts as a translator between the operating system and the hardware devices. When a computer's operating system needs to communicate with hardware, such as a printer or graphics card, it does so through the device driver, which interprets the commands from the software into a language that the hardware can understand. This allows for proper functioning and interaction between the software applications and the physical components of the computer.

In contrast, while firmware is also involved in hardware communication, it typically refers to the specific programming that directly controls hardware devices. A module generally refers to a self-contained component within software that performs a particular task but does not directly facilitate communication with hardware. A software development kit (SDK) includes tools for building software applications but does not specifically handle the interfacing of hardware and software. Thus, the device driver is the key component that directly facilitates this essential interaction.