How E-Mails and Web Sites Work

E-mails were the first use of the Internet back in 1971, long before Web sites existed. The Internet was created by connecting many computers to wired networks so that each computer could receive information from other computers digitally. The networks rely on switches (routers) that direct the little boats (digital packets) on their way through the Internet to their destinations. Packets hold the information contained in e-mails, Web sites, video, or telephone conversations.

A packet can leave one computer and travel halfway around the world through many different networks and arrive at another computer in a second or two. To create an Internet packet, for example, the packet software (called a “client”) breaks up the message into packets of about 200 bytes. A byte consists of eight bits (a bit is a zero or a one). Each packet is put into a frame that contains extra bits with the information necessary for routing the packet from one computer to another.

The main advantage of packet-switching is that it allows millions of computers or mobile phones to use the same network of communication lines. Sharing allows for very efficient use of the worldwide network.

With the Internet, computers aren’t connected directly to other computers. Instead, each packet is independently routed over common lines to its destination. When a packet is ready, the host computer sends it over a telephone line or cable to a router. The router examines the destination address in the frame and passes the packet along to another router, chosen by a route-finding system.

A packet may go through a few or thousands of routers in its travels from one computer to another.

When the packets reach their final destination, they are reassembled in the correct numerical order at the destination computer.

An example of one of the billions of electronic packets that whiz constantly through the internet

This figure illustrates one of the billions of electronic packets that travel every minute of the day all over the world on the Internet. The packet begins and ends with an electronic flag so that the routers can know where each packet begins and ends. It has an electronic address of the destination computer and a packet number with control bits to ensure that the data in the packet is not corrupted. The payload is a group of bits that contain the information that the packet is transporting from the source to the destination computer. This information may be a little section of a Web page, of a TV picture and sound, of a VoIP voice conversation, or of an e-mail.

All packets travel at close to the speed of light: 186,000 miles per second. Because of the various lines and routers involved, a packet may take a few seconds to get where it is going.

How HTML Works

HTML (hypertext markup language) is the language used to create the colorful e-mails and Web sites we are all familiar with. The images shown in a typical HTML e-mail or Web site as they appear on your PC or mobile device may not actually be in the e-mail itself. They may be located on the server of the company sending the e-mail or Web site images. Each image has its own particular internet address called a URL (uniform resource locator). When you open an e-mail or a Web site, your computer sends a packet to the URL asking for certain images in the e-mail or Web site. Each packet has information that says, in effect, “Arthur Hughes has just opened the e-mail we sent him and wants to see this image.” The packet races through the Internet to the location (the URL) where the image is stored. The sending company’s server sends the image back to Arthur in one or more packets and also notes that “Arthur Hughes has just opened his e-mail.” When the packets with the images arrive at your PC, the HTML code converts them into a picture or drawing which you see on your screen.

As you can see, two things happen at once: the delivery of the images and the knowledge of what the e-mail or Web site viewers are doing. The packets sent back to the company contain the address of your computer or mobile device. The address is essential so that the image can be sent back to the PC that is requesting the image. Because of this address, every time a user opens an HTML e-mail or Web site, the sender knows the e-mail or Web site has been opened, who opened it, and when. When you click on a link in an HTML or text e-mail (e.g., to see a different page or section of the e-mail), you see new information because a packet has been sent to the server asking for the new page. The server sends it and records the fact that you clicked on a link. Packets sent back may also include your input (such as your name, a product order, or your response to a survey question).

Many times the recipient’s messaging client (such as Outlook) is set up to protect the recipient’s privacy. If this is the case, the user may see a yellow line at the top of the e-mail that lets the user know that the images have been blocked. When you click on that notice to unblock the images, you are also sending a message to the e-mail sending company that you have done something with the e-mail (opened, clicked, downloaded, etc.). The messaging client (such as Outlook) puts the subject and from line of each e-mail in an in-box—a list of all messages that have arrived for you. The in-box displays the message headers: who sent the mail and the subject of the mail. It may also tell you the time, date, and size of the messages. You can use the header to select the messages you want to read, to skip, to delete, or to mark as “junk” or spam.

Think of how different all of this is from direct mail. With direct mail letters, postcards or catalogs, you have no idea of what your customers are doing with them. They may have read them or chucked them out. Or the postal carrier may not have even delivered them! With e-mail you know that your message has been received and opened (if it was) and that the links were clicked on (if they were)—by whom and when.

Arthur Middleton Hughes, vice president of The Database Marketing Institute, has presented 28 seminars on database and email marketing.  Arthur has also authored several books includingStrategic Database Marketing 4^th Edition (McGraw-Hill 2012). He and Andrew Kordek, chief strategist and co-founder of Trendline Interactive, are hosting a two-day Email Strategy Study Group in Fort Lauderdale  March 26-27, 2013, featuring group competition for email marketers responsible for subscriber acquisition, lifetime value, ratings and reviews, boosting their email budget, and doubling their ROI.  To learn how to attend the Study Group,click here.

Post Footer automatically generated by Add Post Footer Plugin for wordpress.