Horia Varlan / CC BY 2.0 / Flickr
What Is an Email Username?
The username identifies a specific person or address in a domain.
Whoever sets up your email address (you, your school, or your employer) selects the username.
Horia Varlan / CC BY 2.0 / Flickr
Usernames used in a professional capacity usually employ a standardized format.
For example, a company might use your first name, such as Bill@example.com.
This is friendly and easy to remember.
It also affords you some anonymity by not exposing your last name.
For professional accounts, the domain name is usually the name of the company or organization.
Domains on the internet follow a hierarchical system.
Within each top-level domain, custom names are assigned to people and organizations applying for them.
The domain owner can then set up sub-level domains freely, to form a name like bob.example.com.
Which Characters Are Allowed in Email Addresses?
In the standard’s parlance, the username in an email consists of words, separated by dots.
A word in an email address is called an “atom” or quoted string.
A quoted string begins and ends with a quotation mark (").
Backslash characters can also be used in email addresses, but they perform a different function.
