E-MAIL is one of the most useful personal and business communication tools currently available, and networking your computers makes it possible to send e-mail to any user in your organization. This tutorial tells you what e-mail exactly is and examines the various types of e-mail services.

　　E-mail is a client/server application that enables network users to exchange text messages and data files. Workstations run an e-mail client that provides an interface in which a user specifies the address of the intended recipient and enters a message. The client program sends the message to an e-mail server, which relays it to the client program on the recipient’s workstation.

　　Internal e-mail is an application that is limited to use on the local network. Typically, an internal e-mail system consists of a single server and a client on each workstation. Each user has an account on the server that enables them to send and receive e-mail to other clients. On a home or small business network, internal e-mail may be limited in its usefulness because the clients are few and often close enough together not to need e-mail.

　　Large networks typically use products like Microsoft Exchange and Lotus Notes for internal e-mail, which also provide a number of other services. For a small network, Windows 98 includes Windows Messaging, which provides a client interface and the ability to create a mail server called a “postoffice” on a Win98 system.

　　Internet e-mail is based on a standardized addressing scheme and a set of services and protocols that enable users on virtually any computing platform to communicate with virtually anyone. Small networks nearly always use mail servers provided by their ISP (Internet Service Provider). When you connect your network to the Internet, access to the servers is usually included in the fee.

　　Internet e-mail relies on servers scattered all over the Internet, providing various services. An Internet e-mail address consists of user and domain names, in the form user@domain.com. Every domain has an SMTP (Simple Message Transfer Protocol) mail server that receives e-mail addressed to that domain. The DNS (Domain Name Server) records for the domain identify the IP address of the mail server, so that traffic can be routed to the right location. A POP3 (Post Office Protocol) server for the domain maintains mailboxes for users, from which they retrieve their mail.

　　Because Internet e-mail is more standardized, users can choose between many client programs that provide basic e-mail functionality, along with different sets of additional features. Windows 98 includes Outlook Express as part of the Internet Explorer package, which is a combination client for Internet e-mail and Usenet news. Microsoft Outlook, included in the Office package, is a more comprehensive client for both internal and Internet e-mail.  (SD-Agencies)