E-mail address
An e-mail address identifies a destination for E-mail. Generally, an Internet e-mail address (using SMTP or Usenet) is a string of the form jsmith@example.com. It should be read as "jsmith at example dot com". The part before the @ sign is the local-part of the address, often the username of the recipient, and the part after the @ sign is the domain-part which may be a host name or domain name. Each student, support staff member, administrator, and faculty member at Gustavus is issued a unique username with 8 or fewer characters. The domain name for Gustavus e-mail is @gustavus.edu or @gac.edu. Either ending will send the e-mail properly.
Username vs. e-mail address
It's important to note the difference between an e-mail address and a username.
A Gustavus username is just the first part of an e-mail address, without the "@gustavus.edu" part. Whenever you log into any online Gustavus resources, such as the Gribly, your username should not contain the "@gustavus.edu" part.