Home > Articles > Home & Office Computing

Email Basics

John Dvorak covers the basics of email, including attachments, archiving, etiquette, and dreaded spam.
This chapter is from the book

This chapter is from the book

"One of these days there will only be email."

--John C. Dvorak, writing in InfoWorld, 1982

Email is an incredible telecommunications medium to let you exchange messages with others, from one computer to another. It's the most frequently used application on the Internet. According to International Data Corporation (IDC), 5.1 billion emails were sent every day in 2000 in the United States alone. The world daily tally was over 8.2 billion. IDC projects that by 2005, the number will be around 11.5 billion messages a day in the United States and over 26.1 billion worldwide. In the United States, there are 300 million email destinations. About 90 million Americans use email at work routinely. Fifty million Americans have email at home. Of those, the average home has four different email addresses (presumably one for each member of the family).

The Roots of Modern Email

Although early networking systems and the ARPANET had email systems, the roots of the commercial email we know today were first introduced to the public as proprietary services. If you wanted to send email to a friend, you both had to subscribe to the same service and use the same software. These were "dialup" systems. None of the systems were cross-connected systems with any reliability. There were no addresses as we see today (the @ sign wasn't heard of). The proprietary systems included: MCI Mail, EasyLink, Telecom Gold, One-to-One, and CompuServe.

Most people exchanged messages and information on bulletin board systems (BBSs), in forums, and directly by modem to modem. It wasn't that difficult to call a telephone number, connect your modem, and download or upload files. (At their height, there were tens of thousands of BBS systems. Yes, people did communicate without the Internet.) Modem speeds were a big factor in connections. The earliest pre-email connections were able to transmit only about 180 words a minute (150 bits per second [bps]).

Modem speeds climbed quickly, jumping in increments of 150 bps to 14,400 bps, to a current rate of 56 Kbps.

At about the same time, companies were experimenting with Local Area Network (LAN) systems, connecting various personal computers together, sometimes with mainframes. They developed LAN-based email systems. These connected to the mainframe, or central computer, and used a terminal emulation mode, so essentially the personal computers were used as terminals had been used before. However, the email programs became more complex yet easier to use. Company networks evolved. The Internet evolved.

As the Internet became available to more people—both corporate and private—email evolved from proprietary email systems. The key innovation was an evolution in protocol from a variety of protocols to SMTP (Simple Mail Transfer Protocol), which is the main protocol in use today.

Each Internet domain has a corresponding email server. To send an email message to someone, your email client first contacts the addressee's email server, based on rules of the SMTP. First, your server asks the other server whether there is anyone there by that email address. If so, it asks to transfer the email, and the receiving server stores it until the addressee retrieves it. The most common SMTP server in use is the sendmail system, but there are others.

Neither Snow nor Rain nor Heat nor Gloom of Night...

We all have some idea how the United States Postal Service (USPS) works. You put a stamp on an envelope and drop it into a delivery box. It's then sorted, trucked or flown to the right area, then sorted again, and taken out to be delivered. Email is based on the same premise.

When you click Send to launch an email, it is directed to the hosted mail servers (typically, this is a server located at your Internet Service Provider's [ISP's] server location). The message is then sent to the recipient's mail servers. Along the way, the message will bounce off sometimes dozens of other servers. Each server will look at the domain name portion of your intended recipient's email address and will route it to the proper place. The message will finally be delivered to the intended receiver's virtual mailbox residing on the mail servers, where it will sit until the intended recipient checks for email from a local mail client application or from the Internet, if Web mail is available.

Electronic mail messages are not sent in their entirety across the network. They are broken down by the transmission protocol into smaller individual components called data packets. They are then packaged, relayed across the network, and finally reassembled again just short of delivery. When each message is broken down, it is given a unique identification signature. The servers used to relay the packets from point A to point B know where to send each and every one. This is the reason email messages don't collide while in transit. Each unique signature has encoded information indicating the packet size, the origin, destination, sequence data, and encryption coding that's used to construct the packets.

Timing is important when relaying information across a network. Data packets are more likely to become corrupted in transit, rather than run the risk of a collision. To help alleviate the chances of collision and minimize the risk of data corruption during packet transfers, timing sequence algorithms are used. One of the reasons files and messages are broken into smaller packages is their transfer rate of speed. Data packets can be dispersed more quickly in smaller bundles. If data corruption occurs, it's faster for the mail server to resend a single smaller packet than to resend the entire message. If data corruption does occur—usually due to static line noise—the affected packets can be resent out until the entire message is reconstructed at the receiving end.

Anatomy of an Email Address

Each email address is expressed as: name@domain

Each name is unique to a domain. An email address such as bob@address.net, although simple, has all the information needed to get it to its destination. The domain name is not the "real" name. It's an alias because we're better at remembering names than long strings of numbers. Mail servers translate this domain name into the IP (Internet Protocol) address. Every computer on the Internet has a unique numerical address used to route packets to it. Just like your postal address allows the USPS to deliver mail to your house, your computer's IP address gives the network routing protocols the information they need. The receiving server will only have one "bob"; there is only one address.net on the Internet, and it cannot to be confused with address.com, address.org.

When you send email, the email servers use the Internet's standard DNS (Domain Name System) to find the IP address. The DNS maps the domain names to IP addresses. (The job is distributed among a number of servers so that none are overloaded and there is room for growth.) You can find out your IP address on a Windows computer by opening DOS or the command prompt and typing winipcfg or ipconfig. On a Macintosh, you can check your Network control panel.

You can also find your IP address at these Web sites:

  • IP Info—http://www.lawrencegoetz.com/programs/ipinfo

  • The Proxy Connection—http://stealthtests.lockdowncorp.com

  • Privacy Net—http://privacy.net/analyze

Your IP Address

The IP address is broken down into 4 bytes of information (totaling 32 bits), expressed as four numbers between 0 and 255, separated by periods. There are more than 4 billion possible IP addresses. There are several databases to look up a particular IP address to see what information is available on the address:

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020