Overview
Electronic mail, or email, is a form of communication in which electronic messages are created and transferred between two or more devices connected to a data communications network. Electronic communication is one of the most popular forms of business communication, and for many people it is the primary reason they use the Internet. Email travels to its destination across the network to the recipient’s account on a mail server. For many personal and business reasons, people rely on email as an indispensable form of written communication.
Similar to how webpages and files move across networks, email messages also use protocols that send and receive them on networks. The two most common protocols for sending and receiving email messages are POP and SMTP, which are both described in the image below. Two additional protocols, IMAP and MIME, also handle email messages. IMAP (Internet Message Access Protocol) stores mail messages on a remote server so you can view them on your device as if those messages were stored on the device. MIME (Multipurpose Internet Mail Extensions) specifies how to encode nontext data, such as graphics and sound, so it can travel over the Internet.
When an email message arrives at its destination mail server, the mail server’s software handles the details of distributing the message locally, in the same way that a mailroom worker opens a mailbag and places letters and packages into individual mail slots. To check for new email messages, you use an app on your Internet device—which might be a computer, smart phone, or tablet—to request stored mail from the server. The software that requests mail delivery from the mail server to an Internet device is known as mail client software, an email program, or an email app.
An email address uniquely identifies an individual or organization that is connected to the Internet. To route an email message to an individual, you must identify that person by his or her account name, or username, and also by the name of the mail server that manages email sent to the domain. The two parts of an email address—the username and the domain name—are separated by an “at” sign (@). Sharon Kikukawa, for example, selected the username “sharonkikukawa” for her email account. Balloon Adventures uses Google as its email provider, which uses the domain name “gmail.com.” Therefore, Sharon’s email address is sharonkikukawa@gmail.com.
A username identifies a person’s email account on a mail server. When you are given an email address from an organization, such as your school or an employer, the organization might have standards for assigning usernames. Some organizations set standards so usernames consist of a person’s first initial followed by up to seven characters of the person’s last name. Other organizations assign usernames that contain a person’s first and last names separated by an underscore character (for example, sharon_kikukawa). When you are given the opportunity to select your own username, you might use a nickname or a name containing numbers, such as sharonkikukawa0930, to identify yourself. On a mail server, all usernames must be unique.
The domain name is the second part of an email address and specifies the name of the server to which the mail is to be delivered on the Internet. Domain names contain periods, which are usually pronounced as “dot,” and are used to divide each part. The most specific part of the domain name appears first in the address, followed by the top-level domain name. For example, the website address for the National Aeronautics and Space Administration, or NASA, is “nasa.gov” and is pronounced “NASA dot gov.” NASA’s domain name contains only two names separated by a period. The gov in the domain name indicates that this entity is a government organization or program. The nasa indicates the domain name associated with the IP address for NASA.
Most email addresses aren’t case sensitive; for example, the addresses sharonkikukawa@gmail.com and SharonKikukawa@Gmail.com are the same. It is important for you to type a recipient’s address carefully; if you omit or mistype any character, your message could be undeliverable or sent to the wrong recipient. When a message cannot be delivered, the receiving mail server usually returns the message to the sender and indicates that the recipient is unknown. Sometimes mail that cannot be delivered is deleted on the receiving mail server without notifying the sender.
Managing More Than One Email Address
Keep in mind that an email account assigned to you by your school or employer is subject to the rules of use that the organization has established. Some schools and most employers have policies that dictate the permitted use of their equipment and email accounts. You should not use your employer’s email address for personal correspondence unless your employer specifies that your personal use of the email account and your workplace computer is acceptable. In some cases, an employer might discipline employees who abuse the company’s resources for personal use. In many cases, email is subject to monitoring by the organization, so messages you send with your organization-sponsored account are not guaranteed to be private.
For this reason, many people have more than one email address to manage their correspondence. It is very common for people to have a primary email address that they use for business correspondence, as well as a secondary email address that they use for personal correspondence, including messages, online subscriptions, and purchases. If you are careful about how you distribute your primary email address, you might reduce the amount of unsolicited mail that you receive. When your secondary email address starts getting a lot of unwanted messages, you can discontinue it and create a new one. If you keep track of who has your secondary email address, it will be easy to update your contacts if you need to change it.