Zone AF
An area mode in which the camera selects automatically from a defined cluster of points rather than the whole frame.
In depth
Zone AF is the compromise between the precision of a single point and the ease of full-area selection: the photographer decides roughly where the subject is, and the camera handles the fine positioning within that region. It suits sports and wildlife, where holding a single point on a fast, unpredictable subject is unrealistic.
Examples in practice
A zone placed on the right third of the frame keeps focus on a footballer moving within it, ignoring the crowd behind.