where the first part
name) identifies a unique user
. The '@' separates the user name from the host name which uniquely identifies the mail server
. The three-letter suffix following a period
(dot) identifies the kind of organization
operating the mail server. Addresses outside the US use another (two-letter) suffix that identifies the country
where the mail server is located. By convention
, all email addresses are typed in lower-case (common letters) without any spaces separating the different parts.