A display screen in which the top and bottom areas (or left and right areas with a vertical split) of the screen face may be treated as separate screens for the purpose of data manipulation. The split is usually into two parts, not necessarily equal, but there may be more. One part may be used for entering data from the attached keyboard while the other part displays instructions or prompts. The entered data may be manipulated by scrolling or erasing without affecting the other part of the screen. See also window.