email electronic mail Whenever you send messages to people using a computer and they read it later, you've sent a piece of email. You can send email in several ways--across a local area network, via the Internet, or through an online service like CompuServe or America Online--and you can send it to a single recipient or to a whole slew of them. But all email behaves pretty much the same way: you send it to a virtual mailbox, and the recipient has to pick it up or can use software that does it automatically. See also: snail mail, spam