What does the following code do?

CREATE OR REPLACE TRIGGER T

AFTER DELETE

BEGIN

INSERT INTO orders_a

( order_id,

quantity,

cost_per_item,

total_cost,

delete_date,

deleted_by)

VALUES

( :old.order_id,

:old.quantity,

:old.cost_per_item,

:old.total_cost,

sysdate,

user );

END;