An email message is a digitally transmitted text message that is sent between electronic devices through an email client. As of 2014, commonly used email clients include Microsoft Outlook, Yahoo and Gmail. An email is sent using the @ sign to denote the machine or user receiving it.
A simple email interacts with an email server that contains data, such as email account names that are registered to it. Each account also has a text file associated with it that contains a record of messages received. A basic email text string appears in this file with both the sender and receiver name codes appended in front of it. Other information that can be found in this text file includes the email subject line and the date and time of receipt.
More complex email servers, such as an SMTP, POP3 or IMAP servers, can include more in-depth features, such as allowing organization of received emails into folders or tags.
The first email message was sent by engineer Ray Tomlinson in 1971. Initially, emails were only able to be sent between a single sending and receiving machine. Email servers as of 2014 allow for multiple recipients as well as functions such as carbon copy or blank carbon copy recipients.