When displayed on your screen this character will be expanded into the necessary number of spaces to move to the next tab stop. Tab stops are fixed at every four columns with the first stop set on column five. You can display tabs by turning on option tabs display (ot+).
Tabs are not treated with any special significance internally. They only affect your display and your cursor movement on the display. You can not position your cursor on the expanded spaces following the tab, only the tab character itself or the real character following it.