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    Sure, you use e-mail everyday of the week, but what do you really know about the technology that has profoundly changed how we communicate.

    Short for electronic mail, e-mail is the transmission of messages over communications networks. These messages can be notes entered from the keyboard or electronic files stored on disk. Most mainframes, minicomputers, and computer networks have an e-mail system. Some e-mail systems are confined to a single computer system or network, but others have gateways to other computer systems, enabling users to send electronic mail anywhere in the world.

    Internet E-mail

    As reported by the research firm IDC, about 31 billion e-mailsare sent worldwide every day and that number is expected to rise to more than 60 billion by 2006. With the capability to send pictures, documents or even video messages to anyone in the world who has an e-mail address, it has become a massively popular form of communication. For many it has replaced traditional communication methods such as telephone conversations, facsimiles and even postal mail.

    How Does Sending & Receiving E-mail Work?

    Using an e-mail client (software such as Microsoft Outlook or Eudora) you can compose an e-mail message and send it to another person anywhere, so long as you know their e-mail address. All online services and Internet Service Providers (ISPs) offer e-mail, and support gateways so that you can exchange e-mail with users of other systems. Usually, it takes only a few seconds for an e-mail to arrive at its destination. This is a particularly effective way to communicate with a group because you can broadcast a message or documentto everyone in the group at once.

    Although different e-mail systems use different formats, there are some emerging standards that are making it possible for users on all systems to exchange messages. In the PC world, an important e-mail standard is MAPI. The CCITT standards organization has developed the standard, which attempts to provide a universal way of addressing messages. To date, though, the de facto addressing standard is the one used by the Internet system because almost all e-mail systems have an Internet gateway.

    When you initially set-up your e-mail client you will need specific information from your ISP, such as your network user ID, SMTP and POP server address. The network ID will provide you with your e-mail address, the SMTP server handles the communications as you send an e-mail message, and the POP server provides the transmission for receiving e-mail.

    SMTP – Simple Mail Transfer Protocol

    When you send an e-mail message, your e-mail client connects to your ISP’s mail server, which is an SMTP (Simple Mail Transfer Protocol) server. It is common for your e-mail message to be broken down into small packets of data (for a speedier transmission), which is reassembled when it reaches its destination. The SMTP server will generally hand-off the message to another server that is able to translate the domain name of the recipient’s address and find the correct IP addressto deliver the message to. This process may be repeated multiple times until the e-mail is routed to the correct destination server.

    POP – Post Office Protocol

    While SMTP provides the protocol for sending an e-mail, it is a different server that receives your e-mail at your ISP. POP, short for Post Office Protocol, is a protocol used to retrieve e-mail from a mail server. Your ISP will have set up a mailbox on the POP server for all its customers. When incoming e-mails are received by the POP server, it is then filtered down to the correct user mailbox. When you use your e-mail client and connect to the POP server, you log in with your ID (network username), which allows the server to locate your mailbox. Access to the contents of the mailbox is granted by entering in your password. The POP server will deliver your e-mail to your local systemand will delete the messages from the server as well.

    Most e-mail applications use the POP protocol. There are two versions of POP. The first, called POP2, became a standard in the mid-80’s and requires SMTP to send messages. The newer version, POP3, can be used with or without SMTP. While most people will refer to POP with a version number (e.g. POP3), when using the term POP without a number, like any other protocol, it is generally assumed you would be referring to the most recent version anyways.

    IMAP: Internet Message Access Protocol

    The Post Office Protocol is designed to be a simple protocol offering only a basic set of commands, and it is still the most widely used protocol. Similar to POP is IMAP(Internet Message Access Protocol), which is also a protocol for retrieving e-mail messages, but supports some features not found in POP. For example IMAP allows you to search e-mail messages for keywords while the messages still reside on the server. You can also store messages on the e-mail server, and better manage multiple accounts and set message flags. IMAP was developed at Stanford University in 1986.

    Web mail vs. POP Mail

    Web mail is a Web page interface used to access e-mail through a Web browser. In order to use Web mail, your ISP needs to provide this service or you can get a subscription to a Web mail service (some free, some paid subscriptions). Web mail is a secure Web page that you load in your Web browser and log in by entering your username and password. Web mail is popular as it allows you to send or receive e-mail from anywhere, so long as the computer you are using is connected to the Internet and has a Web browser. It is an excellent option for those traveling or working outside the office.

    Web mail systems differ depending on the service provider, but you can expect to find some common features on most systems. Web mail is left on the server, and as a result you’ll usually find anti-virus support and built-in spam filters, which you have some editing control over. Most Web mail systems provide an address or contact book, folders for filing e-mail, and some may provide POP mail retrieval allowing you to check your Web mail account through any e-mail client. This, however, is not a more common Web mail feature and if you use a free Web mail service, this is probably something you’ll only get with an upgraded (paid) subscription.

    While benefits of Web mail are plenty and the systems very easy to use, Web mail does have some disadvantages. The amount of space you can have on the system may be limited (meaning you have to occasionally delete e-mail messages and attachments) and you may experience slow connections to the Web mail service provider during peak Internet usage times. Lastly, one big disadvantage to Web mail is experienced mainly by those using a slower modem connection and by those paying per minute or those who have a limited Internet usage time. To use Web mail you must be connected to the Internet to read or compose more than one e-mail message although it is possible to write your e-mail messages offline in and cut and paste the messages after you’ve logged on and into your Web mail account to save time and money for those not using a dedicated broadband Internet account .

    Common E-Mail Problems and Issues


    There is no doubt that one of the biggest black clouds hanging over e-mail is spam. Spam can be considered any electronic junk mail (generally e-mail advertising for some product) that is sent out to thousands, if not millions, of people with an e-mail address. In addition to wasting people’s time with unwanted e-mail, spam also eats up a lot of network bandwidth. Consequently, there are many organizations, as well as individuals, who have taken it upon themselves to fight spam with a variety of techniques. But because the Internet is public, there is really little that can be done to prevent spam, just as it is impossible to prevent junk mail.

    Many individuals are able to use spam filters in their e-mail clients to help filter some of the annoyances out of their inbox, but for some corporations more strict anti-spam measures are needed because of the sheer volumes of junk mail that must be filtered out of legitimate customer e-mail. Microsoft, for example, receives about 10 million e-mails per day via the Internet. Of those 85 to 90 percent is filtered out as spam. Having an e-mail client download this huge number of spam mail would simply take too long. For this reason many corporations and companies will use spam filters at the server level (instead of the client) to help keep the spam e-mails from ever reaching an employee’s computer.


    It is becoming increasingly common to tune in to the news or load your favorite news Web site and read about yet another Internet e-mail scam. An e-mail scam is a fraudulent e-mail that appears to be from a legitimate Internet address with a justifiable request usually to verify your personal information or account details. One example would be if you received an e-mail that appears to be from your bank requesting you click a hyperlink in the e-mail and verify your online banking information. Usually there will be a repercussion stated in the e-mail for not following the link, such as “your account will be closed or suspended”. The goal of the sender is for you to disclose personal and (or) account related information. This type of e-mail scam is also called phishing. [ Read more about Phishing and how to combat it here

    Changing E-mail Addresses

    Much like changing your postal mail address, having to change an e-mail address requires planning. If you know ahead of time that you will be switching to a new ISP, changing schools, or jobs, it is important to notify your contacts of your new e-mail address. One easy way to help make the switch is to take advantage of using an e-mail signature (see below). This way every e-mail you send will provide details on your new contact information.

    Unless your provider is able to forward your e-mail to a second e-mail address, you alone have to take on the responsibility of making sure people know how to contact you. If it is possible you can try to keep the old e-mail address and use it to send out an automatic responder. When a person sends an e-mail to the old address, they would receive an e-mail notification with your new e-mail address and contact information. One way to avoid changing an e-mail address is to use a Web mail service which is ISP-independent, and would be available to you for a much longer period of time (unless the Web mail service provider goes out of business of course).

    E-mail Headers

    In many disciplines of computer science, a header is considered a unit of information that precedes a data object. The first part of an e-mail message containing controlling and meta datasuch as the subject, origin and destination email addresses, the path an email takes, or its priority. The header will contain information about the e-mail client, and as the e-mail travels to its destination, information about the path it took will be appended to the header. When sending e-mail there are a few standard areas on the message composition window which you need to fill out to ensure correct delivery of your e-mail. These key fields are a part of the e-mail header, and are contain specific data you will provide when you compose an e-mail.

    To (or) Recipient

    When sending e-mail this is the field in your e-mail client where you enter the e-mail address of the person you are sending the message to. When receiving e-mail it will display your e-mail address along with the e-mail addresses of any other recipients of the e-mail. To (or) Recipient information is a part of the e-mail header.

    From (or) Sender

    When sending e-mail this is the field in your e-mail client which will show your name or e-mail address as you entered it when setting up your e-mail client. When receiving e-mail it provides you with the the name or e-mail address of the person who sent you the e-mail. The From (or) Sender information is a part of the e-mail header.

    Carbon Copy (or) cc

    When sending e-mail, this area is where you can type in any additional e-mail addresses of people you wish to send a copy of the e-mail to. Using cc will show the e-mail addresses to everyone the message is going to. The carbon copy or cc information is a part of the e-mail header.
    See also copy

    Bcc (or) Blind Carbon Copy

    When sending e-mail, this area is where you can type in any additional e-mail addresses of people you wish to send a copy of the e-mail to. Similar to a carbon copy, you can insert e-mail addresses in this area, but recipients will not see the e-mail address entered in the blind carbon copy field. The Blind Carbon Copy information is a part of the e-mail header.
    See also copy


    When sending e-mail this is the field in your e-mail client where you enter a subject (or title) for the e-mail you are composing. The Subject information is a part of the e-mail header.

    Common E-mail Client Functions

    While simple text editorsused to be the way to send an e-mail, today we have a plethora of software one can choose for sending and receiving e-mail. Each software package will differ slightly but they do offer standard features which are generally the same. For those making a switch from Web mail to an e-mail client you most likely will come across some standard e-mail functions that were referred to by another name on a Web mail system. Here are a few e-mail terms you should be familiar with to help make using a Windows-based e-mail client easier:


    A file attached to an e-mailmessage. When sending an e-mail you are able to send an attachment which is a file separate from the e-mail message itself. An attachment may be an image file, photo, document, or even a video. When you choose to send an attachment, a ‘browse’ window will normally pop-up allowing you to select the file from your hard drive.

    hard bounce

    When e-mailing, hard bounce is used to describe an e-mail that has bounced back to the sender undelivered without having been accepted by the recipient’s mail server. You will usually receive an e-mail telling you that the e-mail did not reach the recipient.


    Forward is an option in your e-mail client which allows you to forward a received e-mail to another recipient. The e-mail will be sent with the body of the e-mail showing as ‘quoted text’. Recipients of a forwarded e-mail can usually tell the e-mail is a forward. Some clients will place the letters “FWD” in front of the Subject field.


    A redirect is similar to a forward, but the body of the text is not normally shown as quoted text. Additionally the From (or) Sender field will show the e-mail address of the original sender, and in brackets after it will show your information. For example if you received the e-mail from “[email protected]” and your e-mail address is “[email protected]”, when you redirect this e-mail to another recipient, the from (or) Sender information might read something like this:

    From: [email protected] ( by way of “Your Name” )

    e-mail signature

    An e-mail signature is a block of text which is appended to the end of an e-mail message you send. Generally, a signature is used to provide the recipient with your name, e-mail address, business contact information, or Web site URL. Some people, however, will use a signature to sign off their e-mail message with a closing statement, funny quote or other message. A signature file, or sig as it is commonly called can easily be created in most e-mail clients. You will have the option to always attach the signature to all outgoing e-mails, or add the signature in specific outgoing e-mails.


    Most e-mail clients provide a way to help you filter junk and spam mail out of your e-mail. A filter will allow you to specify a string of text or keywords found in subject headers which is known to be spam. For example, if you suddenly start to receive junk mail about “Viagra” you can add Viagra to to your filter keyword list to help keep these messages out of your inbox. When you download your e-mail, the filters (as you can have more than one) will file the matching e-mail in a junk box or the trash can, depending on your specifications. Filters can also be based on a sender’s e-mail address or you can be more aggressive in removing probable junk mail by sending everything which does not contain your e-mail address in the To field to the junk mail box. While filters may allow the odd legitimate e-mail to be filtered out, you can have the filter hold these e-mails in a temporary e-mail box in your client, and you can then take a quick look through them at any time before deleting to ensure important e-mail will be read.

    return receipt

    A return receipt is an e-mail notification that informs you when and if the recipient has opened your message. This is one way to know if an e-mail you sent was received. It is important, however, not to rely on this alone for confirmation, because when you receive an e-mail with a return receipt notification, many e-mail clients will allow a user to send a return receipt “now,” “later,” or “never.”


    Reply is an e-mail client function which allows you to send an e-mail reply to a message you have received. By using reply the main e-mail headers are filled in, with the To (or) Sender field information being filled in based on the From (or) Sender information of the e-mail you are replying to. The reply e-mail will usually quote the received message and it will be sent to only the person who sent the initial message.

    reply to all

    Similar to reply with the exception that the new e-mail will be sent to the original sender and anyone listed in the cc field.

    address book (contact list)

    Some e-mail clients will allow you to create an address book in which you can store the e-mail address and contact information for friends, family, and clients. This allows you to easily find an e-mail address and can make sending e-mails to multiple recipients faster (as opposed to typing in each person’s e-mail address one at a time into the To (or) Sender) field.

    Based in Nova Scotia, Vangie Beal is has been writing about technology for more than a decade. She is a frequent contributor to EcommerceGuide and managing editor at Webopedia. You can tweet her online @AuroraGG.

    This article was originally published on July 22, 2005

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