This is a number that indicates the sequence of this submit element within the tabbing order of all focusable elements in the document.

Gives focus from the current submit object, at which time the submit object's onfocus event fires.

Specifies whether the element is available for user interaction. When set to true , the element cannot receive focus or be modified by the user

This is single character key that either gives focus to a submit element or activates a form control or link action.

See input (type="submit").