auto updation of one table through the updation of other tab

Question

how to auto update or insert some of colum's data in one table through the updation of other table actually i made two tables namely 'transaction' and 'shipment' and they have some common columns and i insert data in 'shipment ' table  on runtime now i want to update same columns automatically  in 'transaction' table on runtime ,, how to do this kindly help

regards...