Penguin Mail is the current mail system on Club Penguin to send postcards. About once a month the postcard catalog is updated. From time to time Club Penguin’s system will send a postcard to penguins. It’s usually for membership notices or getting paid for being a tour guide and/or EPF agent. In the past Club Penguin would also send postcards during a party. Here and there the design of a postcard may get slightly modified.