E-mail

E-mail, short for electronic mail and often abbreviated to e-mail, email or simply mail, is a store and forward method of composing, sending, receiving and storing messages over electronic communication systems. The term "e-mail" (as a noun or verb) applies both to the Internet e-mail system based on the Simple Mail Transfer Protocol (SMTP) and to X.400 systems, and to intranet systems allowing users within one organization to e-mail each other. Intranets may use the Internet protocols or X.400 protocols for internal e-mail service supporting workgroup collaboration. E-mail is often used to deliver bulk unsolicited messages, or "spam", but filter programs exist which can automatically delete some or most of these, depending on the situation.

Spelling

Spelling of this term is disputed. Many now regard the word "email" as a perfectly valid and formal word in its own right, and regard the abbreviation "e-mail" as anachronistic. The word "email" is recognized as a valid alternative in some major dictionaries.The computer industry and web sites still use both variants.
Usage examples from prominent style guides:
Chicago Manual of Style (CMS), 15th edition: e-mail. CMS is widely referenced as the standard for technical writing and journalism style guidelines in the United States.
Microsoft Manual of Style for Technical Publications e-mail, explicitly saying "maintain the hyphenation". O'Reilly and Amazon.com assert that "many top notch technical companies, writers, and editors consider the Microsoft Manual of Style for Technical Publications to be a standard in the industry."
IEEE Computer Society recommends hyphenation in e-mail, deferring to the Chicago Manual of Style explicitly, and using it in their own materials.


Usage examples from prominent companies include:
e-mail: CNN, The New York Times, Microsoft, HP,IBM,Dell, Amazon.com, CNET The Times,The Economist
email: Google, Apple, Yahoo!, eBay , The Guardian
Inconsistent: BBC, Intel
The original RFC definitions for the SMTP standard,the POP standard, and the IMAP standard contain neither e-mail nor email, instead using the terms mail and message. Authors of later RFCs for SMTP use the term email (in addition to mail and message). However, the latest RFC for POP uses mail and message. Hyphens sometimes disappear from words originally coined with them after the term has come into widespread use,although many of those words would still have the same pronunciation following normal English rules, such as web-site vs. website, non-zero vs. nonzero. In contrast, email (without a hyphen) following normal rules is not necessarily the same pronunciation as e-mail.Without the hyphen but keeping the same pronunciation, it would not follow pronunciation patterns of typical English words starting with em, such as emphasis or ember.Even the common English words that start with ema (dictionary search) have a short and/or soft e sound: emaciated, emanate, emasculate, emancipate,rather than a separate syllable for a long-e sound as in e-mail.
The sixth edition of the Shorter Oxford English Dictionary removed hyphens from some 16,000 words that previously employed them although many of those were not merging the words, but removals that resulted in splitting original words into two words ("fig leaf", "hobby horse", "test tube", "ice cream").

Origin
E-mail predates the inception of the Internet, and was in fact a crucial tool in creating the Internet. MIT first demonstrated the Compatible Time-Sharing System (CTSS) in 1961. It allowed multiple users to log into the IBM 7094 from remote dial-up terminals, and to store files online on disk. This new ability encouraged users to share information in new ways. E-mail started in 1965 as a way for multiple users of a time-sharing mainframe computer to communicate. Although the exact history is murky, among the first systems to have such a facility were SDC's Q32 and MIT's CTSS.
E-mail was quickly extended to become network e-mail, allowing users to pass messages between different computers by at least 1966 (it is possible the SAGE system had something similar some time before).
The ARPANET computer network made a large contribution to the development of e-mail. There is one report that indicates experimental inter-system e-mail transfers on it shortly after its creation in 1969.Ray Tomlinson initiated the use of the @ sign to separate the names of the user and their machine in 1971. The ARPANET significantly increased the popularity of e-mail, and it became the killer app of the ARPANET.