A keyboard dock is a device that allows you to connect your tablet or smartphone to a physical keyboard. It typically includes a charging port for the connected device and may also include additional ports, such as USB or HDMI, depending on its design. The purpose of a keyboard dock is to provide an ergonomic and efficient way to type on a full-sized keyboard while using your tablet or smartphone. This can be useful in situations where you need to input a lot of text, such as when working on documents or composing emails. Overall, the main function of a keyboard dock is to enhance productivity and convenience for users who rely heavily on their touchscreens for input.