CHAPTER 8 E-MAIL

E-MAIL

E-mail (electronic mail) is the exchange of computer-stored messages by telecommunication. (Some publications spell it email; we prefer the currently more established spelling of e-mail.) E-mail messages are usually encoded in ASCII text. However, you can also send non-text files, such as graphic images and sound files, as attachments sent in binary streams. E-mail was one of the first uses of the Internet and is still the most popular use. A large percentage of the total traffic over the Internet is e-mail. E-mail can also be exchanged between online service provider users and in networks other than the Internet, both public and private.

10 Advantages of Email

1. It's free!

Once you’re online, there is no further expense.

2. Easy to reference

Sent and received messages and attachments can be stored safely, logically and reliably.  It's a lot easier to organize emails than paper.

3. Easy to use

Once you’re set up, sending and receiving messages is simple. That goes for a host of other email functions. Data storage and contacts can be accessed quickly and easily.

4. Easy to prioritize

Incoming messages have subject lines that mean you can delete without opening. How much time does that save compared to ‘snail mail?’

5. Speed

Message to send? Done, under a second! Email is as fast a form of written communication as any.

6. Global

Web based email means you can access your messages anywhere online. Going overseas? Before you go, mail yourself a copy of your passport number, travel insurance details or your accommodation details.

7. Good for the planet

Actually the advantages and disadvantages of email are clear here. Computers themselves aren’t 'green', but email offsets some of the damage by reducing the environmental cost of contact.

8. Info at your fingertips

Storing data online means less large, space taking file cabinets, folders and shelves. You can access information far quicker if you learn how to use email this way.

9. Leverage

Send the same message to any number of people. Adaptations are simple, too. If you have a product or service to sell, email is an effective medium to get your message out.

10. Send reminders to yourself

Do you use more than one account? Email yourself messages from work to home or vice versa. Does the idea of two or more accounts seem complicated? It's not if you know how to manage multiple accounts.

10 Disadvantages of Email

1. Emotional responses

Some emails cause upset or anger. A reply in the heat of the moment can’t be easily retracted, but it can cause lasting damage.

2. Information overload

Too many people send too much information. They cover their backs citing ‘need to know’ as the justification. Learn how to use email effectively and you’ll reduce time wasted on this.

3. Lacking the Personal Touch

Some things are best left untyped. Email will never beat a hand written card or letter when it comes to relationships.

4. Misunderstandings

Emails from people who don’t take the time to read what they write before clicking ‘send’. Time is wasted, either to clarify or, worse, acting on a misinterpretation of the message.

5. No Respite

Your email inbox is like a garden; it needs to be constantly maintained. Leave it and will continue to grow. Ignore it at your peril!

6. Pressure to Reply

Once it’s in your inbox, you feel an ever increasing obligation to act on it. Procrastinating doesn’t making it go away.  Do it, dump it or delegate it.

7. Spam

Having to deal with spam and spoofs is one of the worst avoidable time wasters online.  Use some anti spam software.

8. Sucks up Your Time

Over checking messages is so common, but it is time wasted on a low value, passive activity.  Better to check once or twice a day.

9. Too Long

How long is too long? It’s hard to say exactly, but the longer it goes on, the harder it is to take in. Email is suited to brevity - keep it short and sweet.

10. Viruses

A virus could seriously affect your computer. If you want to know how to use email effectively, it's worth learning how to deal with these.

What is a Mail Server and How Does it Work?

A mail server (sometimes also referred to an e-mail server) is a server that handles and delivers e-mail over a network, usually over the Internet. A mail server can receive e-mails from client computers and deliver them to other mail servers. A mail server can also deliver e-mails to client computers. A client computer is normally the computer where you read your e-mails, for example your computer at home or in your office. Also an advanced mobile phone or Smartphone, with e-mail capabilities, can be regarded as a client computer in these circumstances.

SMTP and POP3 server

When you press the "Send" button in your e-mail program (e-mail client) the program will connect to a server on the network / Internet that is called an SMTP server. SMTP is an acronym for Simple Mail Transfer Protocol and it is a protocol that is used when e-mails are delivered from clients to servers and from servers to other servers.

When you download e-mails to your e-mail program the program will connect to a server on the net that is known as a POP3 server. A POP3 server uses a protocol named POP3 for its communication. That is the reason why it is called a POP3 server and POP3 is an acronym for Post Office Protocol version 3.

How can my e-mail program (e-mail client) find right mail server on the Internet?

When you start your mail program for the first time, you must normally enter e-mail account information before you can use the program. You must for example specify the name of a server for outgoing e-mail and the name of a server for incoming e-mail. It is here you specify which SMTP server and which POP3 server that your mail program will communicate with over the Internet. The servers can be located anywhere on the Earth, but usually they are located in same country as your client computer.

Can I use any mail server I want on the Internet?

No. The Internet service provider (ISP) that you use when you browse the Internet will normally have mail servers that you can access for your e-mails (both incoming and outgoing e-mail) but you can normally not access mail servers that other Internet service provider own. The reason for this is that mail servers only accept certain IP addresses (the IP addresses that the ISPs provides) and if your IP address is outside this range you will be denied access to the server.

There are exceptions, however. In some cases you can download e-mail from POP3 servers provided by other ISPs. They will only check that your username and password is correct. And there exists also standalone email servers on the Internet that works independently of Internet service providers, and through them you can send and receive e-mails if you have access to the username and password. Many web hosting services provide this kind of stand-alone mail servers.

 How do mail servers find each other on the Internet?

When you send an e-mail from your local computer to a mail server, your e-mail has just started it's journey to your recipient. Perhaps your receiver is on the other side of the world, and then it's a very long distance that the e-mail must travel before it arrives to your receivers computer.

Before the mail server that your e-mail program communicates with knows where to deliver the e-mail message it will examine the e-mail address that you have specified as a receiver of the message. The mail server will extract the domain name of the e-mail address and use it to locate the mail server (POP3 server) that your receiver's client computer communicates with. The domain name is found after the "@" character in an e-mail address. If for example the e-mail address is john@abc.com, the domain name is abc.com. By using this domain name as an address the mail server will find which mail server on the Internet to deliver the e-mail message to. When the server has been identified and it has responded that it will accept an e-mail delivery, the e-mail is sent to this server. And next time your receiver logs on to the POP3 server via his/her client computer, your e-mail will be downloaded to the person's e-mail program. Normally all this will take just a few seconds, but if the mail servers or Internet have a lot of traffic at that moment it can take some more time.

CC and BCC

Carbon Copy Section (cc)

·         Send a message to more than one person, all the recipients will see the list of email addresses.

Blind Carbon Copy Section (bcc)

·         The addresses won’t be seen by the recipients.

·         When email is sent to a large group of people who don’t know each other.

MIME

MIME (Multipurpose Internet Mail Extensions) is a standard which was proposed by Bell Communications in 1991 in order to expand upon the limited capabilities of email, and in particular to allow documents (such as images, sound, and text) to be inserted in a message. It was originally defined by RFCs 1341 and 1342 in June 1992.

Using headers, MIME describes the type of message content and the encoding used.

MIME adds the following features to email service:

·         Be able to send multiple attachments with a single message;

·         Unlimited message length;

·         Use of character sets other than ASCII code;

·         Use of rich text (layouts, fonts, colors, etc)

·         Binary attachments (executables, images, audio or video files, etc.), which may be divided if needed.

MIME uses special header directives to describe the format used in a message body, so that the email client can interpret it correctly:

·         MIME-Version: This is the version of the MIME standard used in the message. Currently only version 1.0 exists.

·         Content-type: Describes the data's type and subtype. It can include a "charset" parameter, separated by a semi-colon, defining which character set to use.

·         Content-Transfer-Encoding: Defines the encoding used in the message body

·         Content-ID: Represents a unique identification for each message segment

·         Content-Description: Gives additional information about the message content.

·         Content-Disposition: Defines the attachment's settings, in particular the name associated with the file, using the attribute filename.

Primary MIME types

MIME types, used in the Content-Type header, are used to classify documents attached to an email. A MIME type is comprised as follows:

Content-type: main_mime_type/mime_subtype

A GIF image, for example, has the following MIME type:

Content-type: image/gif

The primary data types, sometimes called "discrete data types," are:

·         text: readable text data text/rfc822 [RFC822]; text/plain [RFC2646]; text/html [RFC2854] .

·         image: binary data representing digital images: image/jpeg; image/gif; image/png.

·         audio: digital sound data: audio/basic; audio/wav

·         video: video data: video/mpeg

·         application: Other binary data: application/octet-stream; application/pdf

MIME types are also used on the Web to classify documents transferred using the protocol HTTP. Thus during a transaction between a web server and a browser, the first thing the web server does is send the MIME type of the file to the browser, so that the browser knows how to display the document.

Encoding formats

To transfer binary data, MIME offers five encoding formats which can be used in the headertransfer-encoding:

·         7bit: 7-bit text format (for messages without accented characters);

·         8bit: 8-bit text format;

·         quoted-printable: Quoted-Printable format, recommended for messages which use a 7-bit alphabet (such as when there are accent marks);

·         base64: Base 64, recommended for sending binary files as attachments;

·         binary: binary format; not recommended.

Since MIME is very open, it can use third-party encoding formats such as:

·         BinHex (a proprietary format belonging to Apple),

·         uuencode,

·         xxencode

Header encoding

The transfer-encoding header is used to specify an encoding format for the message body, but it doesn't solve the problem of encoding headers themselves (such as the message subject).

To encode headers with character sets which use more than 7 bits, such as for including accented letters in an email's subject, the MIME standard offers the following format:

=?charset?encoding?result?=

·         charset represents the character set used,

·         encoding defines the encoding desired with two possible values:

·         Q for quoted-printable

·         B for base64

·         result: text encoded using the method specified.

Below is an example of Quoted-Printable encoding with "Building façade" as the email's subject.

Subject: Building fa=?ISO-8859-1?Q?=E7ade?=

Composite messages

With the MIME type "multipart", the MIME standard allows for composite messages, meaning messages which include multiple attachments, which may even be nested.

To do so, MIME allows for a standard called boundary. This is an arbitrary string defined as an attribute in the Content-type header:

Content-Type: multipart/mixed;

 boundary="------------020005090303070203010601"

Each separator delimits a portion of content beginning with the headers Content-Type and Content-Encoding. It is essential that the value of this separator is not found within the message contents.

There are several types of separators:

·         multipart/mixed defines a series of multiple elements

·         multipart/alternative defines alternatives for the same information, such as a message in either text and HTML format. If the email client is able to display messages with a layout and configured to do so, it will show the HTML version; otherwise, it will display the test version.

·         multipart/parallel defines data present at the same time (such as sound and image).

·         multipart/signed defines a digital signature for message data

·         multipart/related defines related pieces of information

List of MIME types

MIME types are standardized by a group called the IANA (Internet Assigned Numbers Authority). Here is a non-exhaustive list of the most common MIME types.

MIME Type	Type of file	Associated extension
application/atom+xml	Files in ATOM format	atom
application/iges	CAS files	iges
application/javascript	JavaScript files	js
application/dxf	AutoCAD files	dxf
application/mp4	MPEG4 files	mp4
application/iges	IGES CAD exchange format	igs,iges
application/octet-stream	Non-interpreted binary files	bin
application/msword	Microsoft Word document files	doc
application/pdf	Adobe Acrobat files	pdf
application/postscript	PostScript files	ai,eps,ps
application/rtf	Rich text format	rtf
application/sgml	SGML files	sgml
application/vnd.ms-excel	Microsoft Excel spreadsheet files	xls
application/vnd.ms-powerpoint	Microsoft Powerpoint presentation files	ppt
application/xml	XML file	xml
application/x-tar	Compressed tar files	tar
application/zip	Compressed ZIP files	man
audio/basic	Basic audio files	au,snd
audio/mpeg	MPEG audio files	mpg,mp3
audio/mp4	MPEG-4 audio files	mp4
audio/x-aiff	AIFF audio files	aif,aiff,aifc
audio/x-wav	Wave audio files	wav
image/gif	Gif images	man
image/jpeg	Jpeg images	jpg,jpeg,jpe
image/png	Images PNG	png
image/tiff	Tiff images	tiff,tif
image/x-portable-bitmap	PBM Bitmap files	pbm
image/x-portable-graymap	PBM Graymap files	pgm
image/x-portable-pixmap	PBM Pixmap files	ppm
multipart/x-zip	Zip archive files	zip
multipart/x-gzip	GNU zip archive files	gz,gzip
text/css	Style sheet	css
text/csv	Comma-separated text files	csv
text/html	HTML files	htm,html
text/plain	Unformatted text files	txt,g,h,c,cc,hh,m,f90
text/richtext	Rich text files	rtx
text/rtf	Rich Text Format text files	rtf
text/tab-separated-value	Tab-separated text files	tsv
text/xml	XML files	xml
video/h264	H.264 videos	h264
video/dv	DV videos	dv
video/mpeg	MPEG videos	mpeg,mpg,mpe
video/quicktime	QuickTime videos	qt,mov
video/msvideo	Microsoft Windows videos	avi

POP3 and IMAP

POP3 and IMAP are two different protocols (methods) used to access email.

Of the two, IMAP is the better option - and the recommended option - when you need to check your emails from multiple devices, such as a work laptop, a home computer, or a tablet, smartphone, or other mobile device. Tap into your synced (updated) account from any device with IMAP.

POP3 downloads email from a server to a single computer, then deletes it from the server. Because your messages get downloaded to a single computer or device and then deleted from the server, it can appear that mail is missing or disappearing from your Inbox if you try to check your mail from a different computer.

To learn how to get your AOL Mail on your mobile device, please visit our help article AOL Mail: Mobile Mail.

To learn how to access your mail through a third-party email client (like Outlook, Mac Mail, etc.) please visit our help article How do I access my mail through a third-party email client?

Here are the differences between POP3 and IMAP.

POP3 - Post Office Protocol	IMAP - Internet Messaging Access Protocol
You can use only one computer to check your email (no other devices)	You can use multiple computers and devices to check your email
Your mails are stored on the computer that you use	Your mails are stored on the server
Sent mail is stored locally on your PC, not on a mail server	Sent mail stays on the server so you can see it from any device.

 

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Today I learned about the email, every day and almost all people use email intended to communicate with each other no matter near or far. On this topic I 've learned that there are advantages and disadvantages in the email. Basically email we will send directly to the new mail server and delivered to recipients. I can also see where the CC and BCC recipients can see other recipients, while BCC recipient does not know who the other recipients. In this topic I can also tell the difference between IMAP and POP. It is knowledge that is useful to use in the future.