computer

"Email" is short for "electronic mail" (yes, email is an official English word that requires no hyphen). Email is like an old fashioned letter but in electronic format sent from one computer to another. There is no going to the metal mailbox down the road, no envelopes to address and stamps to lick, yet email very much resembles the classic post office mail process. Most importantly: the email recipient does not have to be at their computer for an email to successfully send. Recipients retrieve their email on their own time. Because of this lag between sending and receiving, email is called "non-real time" or "asynchronous time" messaging.