tabindex

An HTML attribute that controls whether an element can receive keyboard focus and its position in the tab order. A tabindex of 0 places an element in the natural tab order, a positive value sets a specific order position, and a negative value (typically -1) allows programmatic focus but removes the element from the tab order. Tabindex is essential for making custom interactive components keyboard accessible, as by default only links, buttons, and form controls are focusable. It was a key enabler for accessible Web 2.0, allowing complex widgets built from generic elements like divs to receive keyboard input.