It is electronic mail, commonly known as email or e-mail, is used to exchanging messages from a sender to one or more recipients. Modern email operates across the Internet or other computer networks.
Email systems are based on a store-and-forward model where the email servers accept, forward, deliver and store messages. Neither the users nor their computers are required to be online simultaneously; they need connect only briefly, typically to an email server, for as long as it takes to send or receive messages.
E-mail has usually two parts separated by ‘@’, data before it is the user name and after it is the domain.