1. A display apparatus, comprising: a display which displays contents; a location recognizing unit which detects distance between the display apparatus and a user; and a control unit which controls the display to determine an area where the user is positioned, based on distance between the display apparatus and the user which is detected through the location recognizing unit; controls the display to display advertising contents to follow the user, when the user is positioned in a first area; controls the display to display advertising contents according to a motion of the user, when the user is positioned in a second area; and controls the display to display a screen for purchase of a product which corresponds to the advertising contents, when the user is positioned in a third area, wherein all points within the third area are closer to a predetermined point on the display apparatus than any point within the second area, such that when the user is positioned closer to the predetermined point than any point within the second area, the control unit controls the display based on the user being positioned in the third area, and wherein all points within the second area are closer to the predetermined point on the display apparatus than any point within the first area, such that when the user is positioned closer to the predetermined point than any point within the first area and further from the predetermined point than any point within the third area, the control unit controls the display based on the user being positioned in the second area, and wherein each point that is within a field of view of the display apparatus is included in one of the first area, the second area, and the third area.