Email is a shorthand term which means: electronic mail. Email is
similar to a regular postal letter; containing an address, routing
information and content. Email uses a range of protocol's - like
IMAP, POP3, SMTP - to route messages from mail servers to users.
Email - as a technology - predates the Internet, and was first implemented
in ARPANET (1973). Email, as a term, can also be written as: e-mail.
The first thing that a user requires to send and receive email messages
is an email address. The majority of Internet Service Provider provide
a free email account to customers;
but there are a plethora of companies who provide free webmail
accounts, such as Gmail and Yahoo!. Email client programs (like
Outlook Express) can be used
to access email accounts.
Anatomy of an Email message
The format of email messages is broken
into two sections: 1) a header, 2) message body.
The header of an email message is more complex, and contains the
information needed to encode and route the email message. The header
can include multiple fields, but four popular fields are:: From:;
To:; Cc:; and Subject:. The two fields which
an email message must include are the From: and Date:
The From: and To: fields are somewhat self explanatory
(email address of the sender and receiver); the Cc: field
is used to send a message to multiple additional addresses (Bcc:
field hides the addresses from other recipients); the Subject:
field is used to describe what is included in the body of the message.
Originally email messages were only plain text, and some mail servers
will only support plain text email messages. However, if the content
type of the email (included in the header) supports MIME: then the
body of the email message can be encoded with HTML elements. Therefore,
the body section of an email message can include plain text and
Anatomy of an Email address
An e-mail address can be broken down into three section, coloured
The first section is the username (editor) which refers to the
recipient's account name at a mail service; also referred to as
the 'local' part of an email address. Secondly there is the @ sign
- which is included in every email address - and means 'at' and
connects the local part of the email address to the hostname of
the email address.
Then comes the hostname (internet-guide), which can also be called
the domain name. This refers to the mail server address: usually
having an individual IP address. The hostname of an email address
can include a range of top-level domain names (TLD). For example,
'co.uk', is for commercial sites based in the United Kingdom.
When sending email messages, it is essential to spell the email
address correctly; just as with a normal postal letter. If the email
address is entered incorrectly, then it will not be sent to the
correct person. If you send an email to an address which does not
exist: then the message will be returned with an "Address Unknown"