Target acquisition

The process of moving a pointer or input device to a specific on-screen element and selecting it, such as tapping an icon, clicking a button, or choosing a menu item. Target acquisition is a fundamental interaction in graphical user interfaces, and its difficulty is influenced by the target's size, distance, and the user's motor abilities. Research has identified specific sources of acquisition difficulty including systematic tap offset (users consistently hitting below their intended target), drifting (accidentally activating adjacent elements when lifting a hand or stylus), and slipping (landing correctly but sliding off before completing the selection). These difficulties increase with age and motor impairment, making target acquisition a key concern for accessible interface design. Guidelines like WCAG recommend minimum touch target sizes of 44x44 CSS pixels to accommodate users with varying motor precision.