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%@!.: Symbolic Cacophony

Email addresses usually appear in one of two forms--using the Internet format which contains `@', an "at"-sign, or using the UUCP format which contains `!', an exclamation point, also called a "bang." The latter of the two, UUCP "bang" paths, is more restrictive, yet more clearly dictates how the mail will travel. invisible.xbm invisible.xbm

To reach Jim Morrison on the system south.america.org, one would address the mail as `jm@south.america.org'. But if Jim's account was on a UUCP site named brazil, then his address would be `brazil!jm'. If it's possible (and one exists), try to use the Internet form of an address; bang paths can fail if an intermediate site in the path happens to be down. There is a growing trend for UUCP sites to register Internet domain names, to help alleviate the problem of path failures. invisible.xbm

Another symbol that enters the fray is `%'---it acts as an extra "routing" method. For example, if the UUCP site dream is connected to south.america.org, but doesn't have an Internet domain name of its own, a user debbie on dream can be reached by writing to the address


The form is significant. This address says that the local system should first send the mail to south.america.org. There the address debbie%dream will turn into debbie@dream, which will hopefully be a valid address. Then south.america.org will handle getting the mail to the host dream, where it will be delivered locally to debbie.

All of the intricacies of email addressing methods are fully covered in the book !%@:: A Directory of Electronic Mail Addressing and Networks published by O'Reilly and Associates, as part of their Nutshell Handbook series. It is a must for any active email user. Write to nuts@ora.com for ordering information. invisible.xbm

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