A keyboard tray is a flat surface designed to hold a computer keyboard and sometimes a mouse. It is typically mounted under a desk, allowing users to slide it in and out as needed. This design helps to save desk space and can promote better ergonomics by positioning the keyboard at a comfortable height. Using a keyboard tray can reduce strain on the wrists and arms, as it encourages a more natural typing posture. Many trays are adjustable, allowing users to customize the height and angle to suit their preferences, which can enhance overall comfort during long periods of computer use.