TAB INSERT - (CTRL/I or TAB)

 Moves the cursor in one of two ways:

     1.  If the tab size has not been set with SET TAB or if the cursor is not
         at the beginning of the line, a tab character is inserted at the cursor
         position.

     2.  If the tab size has been set with SET TAB or if the cursor is at the
         beginning of the line, a number of tab characters and spaces are
         inserted to move the cursor to the column position that is equal to
         the SET TAB value times the indentation level count.