e-mail

Electronic mail is perhaps the most ubiquitous computer application in use today. E-mail can be defined as the send-ing of a message to one or more individuals via a computer connection.

Development and Architecture

The simplest form of e-mail began in the 1960s as a way that users on a time-sharing computer system could post and read messages. The messages consisted of text in a file that was accessible to all users. A user could simply log into the Transmission of an e-mail message depends on widely used proto-cols such as SMTP, which controls message format and processing, and POP3, which handles interaction between mail servers and client programs. As long as the formats are properly followed, users can employ a wide variety of mail programs (agents), and service providers can use a variety of mail server programs. system, open the file, and look for messages. In 1971, how-ever, the ARPANET (ancestor of the Internet—see inter-net) was used by researchers at Bolt Beranek and Newman (BBN) to send messages from a user at one computer to a user at another. The availability of e-mail helped fuel the growth of the ARPANET through the 1970s and beyond.

As e-mail use increased and new features were devel-oped, the question of a standardized protocol for messages became more important. By the mid-1980s, the world of e-mail was rather fragmented, much like the situation in the early history of the telephone, where users often had to choose between two or more incompatible systems. Apranet (or Internet) users used SMTP (Simple Mail Transport Pro-tocol) while a competing standard (OSI MHS, or Message Handling System) also had its supporters. Meanwhile, the development of consumer-oriented online services such as CompuServe and America Online threatened a further bal-kanization of e-mail access, though systems called gateways were developed to transport messages from one system to another.

By the mid-1990s, however, the nearly universal adop-tion of the Internet and its TCP/IP protocol had established SMTP and the ubiquitous Sendmail mail transport program as a uniform infrastructure for e-mail. The extension of the Internet protocol to the creation of intranets has largely eliminated the use of proprietary corporate e-mail systems. Instead, companies such as Microsoft and Google compete to offer full-featured e-mail programs that include group-oriented features such as task lists and scheduling (see also personal information manager).

E-mail Trends

The integration of e-mail with HTML for Web-style for-matting and MIME (for attaching graphics and multime-dia files) has greatly increased the richness and utility of the e-mail experience. E-mail is now routinely used within organizations to distribute documents and other resources. However, the addition of capabilities has also opened secu-rity vulnerabilities. For example, Microsoft Windows and the popular Microsoft Outlook e-mail client together pro-vide the ability to run programs (scripts) directly from attachments (files associated with e-mail messages). This means that it is easy to create a virus program that will run when an enticing-looking attachment is opened. The virus can then find the user’s mailbox and mail copies of itself to the people found there. E-mail has thus replaced the floppy disk as the preferred medium for such mischief. (See com-puter virus.)

Beyond security issues, e-mail is having considerable social and economic impact. E-mail has largely replaced postal mail (and even long-distance phone calls) as a way for friends and relatives to keep in touch. As more com-panies begin to use e-mail for providing routine bills and statements, government-run postal systems are seeing their first-class mail revenue drop considerably. Despite the risk of viruses or deception and the annoyance of electronic junk mail (see spam), e-mail has become as much a part of our way of life as the automobile and the telephone.