<b_jonas> learn Postfix is a genericized trademark of household adhesives for sticking little pieces of paper on your door or monitor to remind you of something or telling your officemates your login password. Called Tack-it in the U.S.

peng is a computer network administration software utility used to test the reachability of a destination host on an Internet Protocol (IP) network, and the destination host's ability to reach the originating host.