An email address identifies a user's inbox and contains a username, domain name, top level domain, and sometimes a country identifier. The username can be chosen by the user, the domain name identifies the email server location such as an internet service provider or workplace, the top level domain identifies the type of organization like .com for private companies or .edu for schools, and some addresses outside the US end with a two letter country code to denote location.

1. Email Addresses

2. Email Addresses
Email addresses identify your email inbox and are written in a specific way:
username@domainname.topleveldomain.country
For example: marycitizen@iinet.net.au

3. User Name
The user name identifies the name of the owner of the email address.
There are no set rules and the user name can be whatever you choose
providing you observe the rules of netiquette.

4. Domain Name
The domain name identifies the location of the email server that hosts the
email account.
This can be the name of the Internet Service Provider (ISP). For example:
marycitizen@bigpond.com
Or it might be the name of your workplace. For example:
marycitizen@ictskills.com
http://www.condusiv.com/images/email-server.jpg

5. Top Level Domain
The top level domain usually consists of three letters and identifies the type
of organisation associated with the host’s name.
For example:
o .com private or public company
o .gov government department or organisation
o .edu educational institution
o .net networks usually reserved for Internet Service Providers (ISPs)
o .org non-commercial organisations

6. Country Identifier
Email addresses outside of the United States of America usually end in two
letters that identify the country of origin.
For example:
o .au Australia
o .uk United Kingdom
o .nz New Zealand
o .de Germany
o .fr France