Debian is a Unix-like operating system consisting of free software. Ian Murdock started the Debian Project on August 16, 1993. Debian 0.01 was released on September 15, 1993, the first stable version, 1.1, was released on June 17, 1996. The Debian stable branch is the most popular edition for personal computers and network servers, is used as the basis for many other distributions. Debian is one of the earliest operating systems based on the Linux kernel; the project's work is carried out over the Internet by a team of volunteers guided by the Debian Project Leader and three foundational documents: the Debian Social Contract, the Debian Constitution, the Debian Free Software Guidelines. New distributions are updated continually, the next candidate is released after a time-based freeze. Debian has been developed and distributed according to the principles of the GNU Project, this drew the support of the Free Software Foundation which sponsored the project from November 1994 to November 1995; when the sponsorship ended, the Debian Project formed the nonprofit Software in the Public Interest to continue financially supporting development.
Debian has access to online repositories that contain over 51,000 packages Debian contains only free software, but non-free software can be downloaded and installed from the Debian repositories. Debian includes popular free programs such as LibreOffice, Firefox web browser, Evolution mail, K3b disc burner, VLC media player, GIMP image editor, Evince document viewer. Debian is a popular choice for servers, for example as the operating system component of a LAMP stack. Debian supports Linux having offered kFreeBSD for version 7 but not 8, GNU Hurd unofficially. GNU/kFreeBSD was released as a technology preview for IA-32 and x86-64 architectures, lacked the amount of software available in Debian's Linux distribution. Official support for kFreeBSD was removed for version 8, which did not provide a kFreeBSD-based distribution. Several flavors of the Linux kernel exist for each port. For example, the i386 port has flavors for IA-32 PCs supporting Physical Address Extension and real-time computing, for older PCs, for x86-64 PCs.
The Linux kernel does not contain firmware without sources, although such firmware is available in non-free packages and alternative installation media. Debian offers CD images built for Xfce, the default desktop on CD, DVD images for GNOME, KDE and others. MATE is supported, while Cinnamon support was added with Debian 8.0 Jessie. Less common window managers such as Enlightenment, Fluxbox, IceWM, Window Maker and others are available; the default desktop environment of version 7.0 Wheezy was temporarily switched to Xfce, because GNOME 3 did not fit on the first CD of the set. The default for the version 8.0 Jessie was changed again to Xfce in November 2013, back to GNOME in September 2014. Several parts of Debian are translated into languages other than American English, including package descriptions, configuration messages and the website; the level of software localization depends on the language, ranging from the supported German and French to the hardly translated Creek and Samoan. The installer is available in 73 languages.
Debian offers CD images for installation that can be downloaded using BitTorrent or jigdo. Physical disks can be bought from retailers; the full sets are made up of several discs, but only the first disc is required for installation, as the installer can retrieve software not contained in the first disc image from online repositories. Debian offers different network installation methods. A minimal install of Debian is available via the netinst CD, whereby Debian is installed with just a base and added software can be downloaded from the Internet. Another option is to boot the installer from the network. Installation images can be used to create a bootable USB drive; the default bootstrap loader is GNU GRUB version 2, though the package name is grub, while version 1 was renamed to grub-legacy. This conflicts with e.g. Fedora, where grub version 2 is named grub2; the default desktop may be chosen from the DVD boot menu among GNOME, KDE Plasma, Xfce and LXDE, from special disc 1 CDs. Debian releases live install images for CDs, DVDs and USB thumb drives, for IA-32 and x86-64 architectures, with a choice of desktop environments.
These Debian Live images allow users to boot from removable media and run Debian without affecting the contents of their computer. A full install of Debian to the computer's hard drive can be initiated from the live image environment. Personalized images can be built with the live-build tool for discs, USB drives and for network booting purposes. Debian was first announced on August 16, 1993, by Ian Murdock, who called the system "the Debian Linux Release"; the word "Debian" was formed as a portmanteau of the first name of his then-girlfriend Debra Lynn and his own first name. Before Debian's release, the Softlanding Linux System had been a popular Linux distribution and the basis for Slackware; the perceived poor maintenance and prevalence of bugs in SLS motivated Murdock to launch a new distribution. Debian 0.01, released on September 15, 1993, was the first of several internal releases. Version 0.90 was the first public release, providing support through mailing lists hosted at Pixar. The release included the Debian Linux Manifesto, outlining Murdock's view for the new operating system.
In it he called for the creation of a distribution to be maintained in the spirit of Linux and GNU. The Debian project released the 0.9x versions in 1994 and 1995. During this time it was sponso
Authentication is the act of confirming the truth of an attribute of a single piece of data claimed true by an entity. In contrast with identification, which refers to the act of stating or otherwise indicating a claim purportedly attesting to a person or thing's identity, authentication is the process of confirming that identity, it might involve confirming the identity of a person by validating their identity documents, verifying the authenticity of a website with a digital certificate, determining the age of an artifact by carbon dating, or ensuring that a product is what its packaging and labeling claim to be. In other words, authentication involves verifying the validity of at least one form of identification. Authentication is relevant to multiple fields. In art and anthropology, a common problem is verifying that a given artifact was produced by a certain person or in a certain place or period of history. In computer science, verifying a person's identity is required to allow access to confidential data or systems.
Authentication can be considered to be of three types: The first type of authentication is accepting proof of identity given by a credible person who has first-hand evidence that the identity is genuine. When authentication is required of art or physical objects, this proof could be a friend, family member or colleague attesting to the item's provenance by having witnessed the item in its creator's possession. With autographed sports memorabilia, this could involve someone attesting that they witnessed the object being signed. A vendor selling branded items implies authenticity, while he or she may not have evidence that every step in the supply chain was authenticated. Centralized authority-based trust relationships back most secure internet communication through known public certificate authorities; the second type of authentication is comparing the attributes of the object itself to what is known about objects of that origin. For example, an art expert might look for similarities in the style of painting, check the location and form of a signature, or compare the object to an old photograph.
An archaeologist, on the other hand, might use carbon dating to verify the age of an artifact, do a chemical and spectroscopic analysis of the materials used, or compare the style of construction or decoration to other artifacts of similar origin. The physics of sound and light, comparison with a known physical environment, can be used to examine the authenticity of audio recordings, photographs, or videos. Documents can be verified as being created on ink or paper available at the time of the item's implied creation. Attribute comparison may be vulnerable to forgery. In general, it relies on the facts that creating a forgery indistinguishable from a genuine artifact requires expert knowledge, that mistakes are made, that the amount of effort required to do so is greater than the amount of profit that can be gained from the forgery. In art and antiques, certificates are of great importance for authenticating an object of interest and value. Certificates can, however be forged, the authentication of these poses a problem.
For instance, the son of Han van Meegeren, the well-known art-forger, forged the work of his father and provided a certificate for its provenance as well. Criminal and civil penalties for fraud and counterfeiting can reduce the incentive for falsification, depending on the risk of getting caught. Currency and other financial instruments use this second type of authentication method. Bills and cheques incorporate hard-to-duplicate physical features, such as fine printing or engraving, distinctive feel and holographic imagery, which are easy for trained receivers to verify; the third type of authentication relies on documentation or other external affirmations. In criminal courts, the rules of evidence require establishing the chain of custody of evidence presented; this can be accomplished through a written evidence log, or by testimony from the police detectives and forensics staff that handled it. Some antiques are accompanied by certificates attesting to their authenticity. Signed sports memorabilia is accompanied by a certificate of authenticity.
These external records have their own problems of forgery and perjury, are vulnerable to being separated from the artifact and lost. In computer science, a user can be given access to secure systems based on user credentials that imply authenticity. A network administrator can give a user a password, or provide the user with a key card or other access device to allow system access. In this case, authenticity is implied but not guaranteed. Consumer goods such as pharmaceuticals, fashion clothing can use all three forms of authentication to prevent counterfeit goods from taking advantage of a popular brand's reputation; as mentioned above, having an item for sale in a reputable store implicitly attests to it being genuine, the first type of authentication. The second type of authentication might involve comparing the quality and craftsmanship of an item, such as an expensive handbag, to genuine articles; the third type of authentication could be the presence of a trademark on the item, a protected marking, or any other identifying feature which aids consumers in the identification o
An email client, email reader or more formally mail user agent is a computer program used to access and manage a user's email. A web application which provides message management and reception functions may act as an email client, "email client" may refer to a piece of computer hardware or software whose primary or most visible role is to work as an email client. Like most client programs, an email client is only active; the most common arrangement is for an email user to make an arrangement with a remote Mail Transfer Agent server for the receipt and storage of the client's emails. The MTA, using a suitable mail delivery agent, adds email messages to a client's storage as they arrive; the remote mail storage is referred to as the user's mailbox. The default setting on many Unix systems is for the mail server to store formatted messages in mbox, within the user's HOME directory. Of course, users of the system can log-in and run a mail client on the same computer that hosts their mailboxes. Emails are stored in the user's mailbox on the remote server until the user's email client requests them to be downloaded to the user's computer, or can otherwise access the user's mailbox on the remote server.
The email client can be set up to connect to multiple mailboxes at the same time and to request the download of emails either automatically, such as at pre-set intervals, or the request can be manually initiated by the user. A user's mailbox can be accessed in two dedicated ways; the Post Office Protocol allows the user to download messages one at a time and only deletes them from the server after they have been saved on local storage. It is possible to leave messages on the server to permit another client to access them. However, there is no provision for flagging a specific message as seen, answered, or forwarded, thus POP is not convenient for users who access the same mail from different machines. Alternatively, the Internet Message Access Protocol allows users to keep messages on the server, flagging them as appropriate. IMAP provides folders and sub-folders, which can be shared among different users with different access rights; the Sent and Trash folders are created by default. IMAP features an idle extension for real time updates, providing faster notification than polling, where long lasting connections are feasible.
See the remote messages section below. In addition, the mailbox storage can be accessed directly by programs running on the server or via shared disks. Direct access is less portable as it depends on the mailbox format. Email clients contain user interfaces to display and edit text; some applications permit the use of a program-external editor. The email clients will perform formatting according to RFC 5322 for headers and body, MIME for non-textual content and attachments. Headers include the destination fields, To, Cc, Bcc, the originator fields From, the message's author, Sender in case there are more authors, Reply-To in case responses should be addressed to a different mailbox. To better assist the user with destination fields, many clients maintain one or more address books and/or are able to connect to an LDAP directory server. For originator fields, clients may support different identities. Client settings require the user's real name and email address for each user's identity, a list of LDAP servers.
When a user wishes to create and send an email, the email client will handle the task. The email client is set up automatically to connect to the user's mail server, either an MSA or an MTA, two variations of the SMTP protocol; the email client which uses the SMTP protocol creates an authentication extension, which the mail server uses to authenticate the sender. This method eases nomadic computing; the older method was for the mail server to recognize the client's IP address, e.g. because the client is on the same machine and uses internal address 127.0.0.1, or because the client's IP address is controlled by the same Internet service provider that provides both Internet access and mail services. Client settings require the name or IP address of the preferred outgoing mail server, the port number, the user name and password for the authentication, if any. There is a non-standard port 465 for SSL encrypted SMTP sessions, that many clients and servers support for backward compatibility. With no encryption, much like for postcards, email activity is plainly visible by any occasional eavesdropper.
Email encryption enables privacy to be safeguarded by encrypting the mail sessions, the body of the message, or both. Without it, anyone with network access and the right tools can monitor email and obtain login passwords. Examples of concern include the government censorship and surveillance and fellow wireless network users such as at an Internet cafe. All relevant email protocols have an option to encrypt the whole session, to prevent a user's name and password from being sniffed, they are suggested for nomadic users and whenever the Internet access provider is not trusted. When sending mail, users can only control encryption at the first hop from a client to its configured outgoing mail server. At any further hop, messages may be transmitted with or without encryption, depending on the general configuration of the transmitting server and the capabilities of the receiving one. Encrypted mail sessions deliver messages in their original format, i.e. plain text or encrypted body, o
Spamming is the use of messaging systems to send an unsolicited message advertising, as well as sending messages on the same site. While the most recognized form of spam is email spam, the term is applied to similar abuses in other media: instant messaging spam, Usenet newsgroup spam, Web search engine spam, spam in blogs, wiki spam, online classified ads spam, mobile phone messaging spam, Internet forum spam, junk fax transmissions, social spam, spam mobile apps, television advertising and file sharing spam, it is named after Spam, a luncheon meat, by way of a Monty Python sketch about a restaurant that has Spam in every dish and where patrons annoyingly chant "Spam!" over and over again. Spamming remains economically viable because advertisers have no operating costs beyond the management of their mailing lists, infrastructures, IP ranges, domain names, it is difficult to hold senders accountable for their mass mailings; the costs, such as lost productivity and fraud, are borne by the public and by Internet service providers, which have been forced to add extra capacity to cope with the volume.
Spamming has been the subject of legislation in many jurisdictions. A person who creates spam is called a spammer; the term spam is derived from the 1970 Spam sketch of the BBC television comedy series Monty Python's Flying Circus. The sketch, set in a cafe, has a waitress reading out a menu where every item includes Spam canned luncheon meat; as the waitress recites the Spam-filled menu, a chorus of Viking patrons drowns out all conversations with a song, repeating "Spam, Spam, Spam… Spammity Spam! Wonderful Spam!". The excessive amount of Spam mentioned, references the preponderance of it and other imported canned meat products in the United Kingdom after World War II, as the country struggled to rebuild its agricultural base. In the 1980s the term was adopted to describe certain abusive users who frequented BBSs and MUDs, who would repeat "Spam" a huge number of times to scroll other users' text off the screen. In early chat rooms services like PeopleLink and the early days of Online America, they flooded the screen with quotes from the Monty Python Spam sketch.
This was used as a tactic by insiders of a group that wanted to drive newcomers out of the room so the usual conversation could continue. It was used to prevent members of rival groups from chatting—for instance, Star Wars fans invaded Star Trek chat rooms, filling the space with blocks of text until the Star Trek fans left, it came to be used on Usenet to mean excessive multiple posting—the repeated posting of the same message. The unwanted message would appear in many, if not all newsgroups, just as Spam appeared in all the menu items in the Monty Python sketch; the first usage of this sense was by Joel Furr This use had become established—to spam Usenet was flooding newsgroups with junk messages. The word was attributed to the flood of "Make Money Fast" messages that clogged many newsgroups during the 1990s. In 1998, the New Oxford Dictionary of English, which had only defined "spam" in relation to the trademarked food product, added a second definition to its entry for "spam": "Irrelevant or inappropriate messages sent on the Internet to a large number of newsgroups or users."
There was an effort to differentiate between types of newsgroup spam. Messages that were crossposted to too many newsgroups at once – as opposed to those that were posted too – were called velveeta, but this term didn't persist. In the late 19th Century Western Union allowed telegraphic messages on its network to be sent to multiple destinations; the first recorded instance of a mass unsolicited commercial telegram is from May 1864, when some British politicians received an unsolicited telegram advertising a dentist. The earliest documented spam was a message advertising the availability of a new model of Digital Equipment Corporation computers sent by Gary Thuerk to 393 recipients on ARPANET in 1978. Rather than send a separate message to each person, the standard practice at the time, he had an assistant, Carl Gartley, write a single mass email. Reaction from the net community was fiercely negative. Spamming had been practiced as a prank by participants in multi-user dungeon games, to fill their rivals' accounts with unwanted electronic junk.
The first major commercial spam incident started on March 5, 1994, when a husband and wife team of lawyers, Laurence Canter and Martha Siegel, began using bulk Usenet posting to advertise immigration law services. The incident was termed the "Green Card spam", after the subject line of the postings. Defiant in the face of widespread condemnation, the attorneys claimed their detractors were hypocrites or "zealouts", claimed they had a free speech right to send unwanted commercial messages, labeled their opponents "anti-commerce radicals"; the couple wrote a controversial book entitled How to Make a Fortune on the Information Superhighway. An early example of nonprofit fundraising bulk posting via Usenet occurred in 1994 on behalf of CitiHope, an NGO attempting to raise funds to rescue children at risk during the Bosnian War. However, as it was a violation of their terms of service, the ISP Panix deleted all of the bulk posts from Usenet, only missing three copies. Within a few years, the focus of spamming moved chiefly to email.
By 1999, Khan C. Smith, a well known hacker at the time, had begun to commercialize the bulk email industry and rallied thousands into the business by building more friendly bulk email software and providing internet access illegally hacked from major ISPs suc
Wired is a monthly American magazine, published in print and online editions, that focuses on how emerging technologies affect culture, the economy, politics. Owned by Condé Nast, it is headquartered in San Francisco and has been in publication since March/April 1993. Several spin-offs have been launched, including Wired UK, Wired Italia, Wired Japan, Wired Germany. Condé Nast's parent company Advance Publications is the major shareholder of Reddit, an internet information conglomeration website. In its earliest colophons, Wired credited Canadian media theorist Marshall McLuhan as its "patron saint." From its beginning, the strongest influence on the magazine's editorial outlook came from techno-utopian cofounder Stewart Brand and his associate Kevin Kelly. From 1998 to 2006, Wired magazine and Wired News, which publishes at Wired.com, had separate owners. However, Wired News remained responsible for republishing Wired magazine's content online due to an agreement when Condé Nast purchased the magazine.
In 2006, Condé Nast bought Wired News for $25 million. Wired contributor Chris Anderson is known for popularizing the term "the Long Tail", as a phrase relating to a "power law"-type graph that helps to visualize the 2000s emergent new media business model. Anderson's article for Wired on this paradigm related to research on power law distribution models carried out by Clay Shirky in relation to bloggers. Anderson widened the definition of the term in capitals to describe a specific point of view relating to what he sees as an overlooked aspect of the traditional market space, opened up by new media; the magazine coined the term "crowdsourcing", as well as its annual tradition of handing out Vaporware Awards, which recognize "products and other nerdy tidbits pitched and hyped, but never delivered". The magazine was founded by American journalist Louis Rossetto and his partner Jane Metcalfe, along with Ian Charles Stewart, in 1993 with initial backing from software entrepreneur Charlie Jackson and eclectic academic Nicholas Negroponte of the MIT Media Lab, a regular columnist for six years, wrote the book Being Digital, founded One Laptop per Child.
The founding designers were John Plunkett and Barbara Kuhr, beginning with a 1991 prototype and continuing through the first five years of publication, 1993–98. Wired, which touted itself as "the Rolling Stone of technology", made its debut at the Macworld conference on January 2, 1993. A great success at its launch, it was lauded for its vision, originality and cultural impact. In its first four years, the magazine won two National Magazine Awards for General Excellence and one for Design; the founding executive editor of Wired, Kevin Kelly, was an editor of the Whole Earth Catalog and the Whole Earth Review and brought with him contributing writers from those publications. Six authors of the first Wired issue had written for Whole Earth Review, most notably Bruce Sterling and Stewart Brand. Other contributors to Whole Earth appeared in Wired, including William Gibson, featured on Wired's cover in its first year and whose article "Disneyland with the Death Penalty" in issue 1.4 resulted in the publication being banned in Singapore.
Wired cofounder Louis Rossetto claimed in the magazine's first issue that "the Digital Revolution is whipping through our lives like a Bengali typhoon," yet despite the fact that Kelly was involved in launching the WELL, an early source of public access to the Internet and earlier non-Internet online experience, Wired's first issue de-emphasized the Internet and covered interactive games, cell-phone hacking, digital special effects, military simulations, Japanese otaku. However, the first issue did contain a few references to the Internet, including online dating and Internet sex, a tutorial on how to install a bozo filter; the last page, a column written by Nicholas Negroponte, was written in the style of an email message but contained fake, non-standard email addresses. By the third issue in the fall of 1993, the "Net Surf" column began listing interesting FTP sites, Usenet newsgroups, email addresses, at a time when the numbers of these things were small and this information was still novel to the public.
Wired was among the first magazines to list the email address of its contributors. Associate publisher Kathleen Lyman was brought on board to launch Wired with an advertising base of major technology and consumer advertisers. Lyman, along with Simon Ferguson, introduced revolutionary ad campaigns by a diverse group of industry leaders—such as Apple Computer, Sony, Calvin Klein, Absolut—to the readers of the first technology publication with a lifestyle slant; the magazine was followed by a companion website, a book publishing division, a Japanese edition, a short-lived British edition. Wired UK was relaunched in April 2009. In 1994, John Battelle, cofounding editor, commissioned Jules Marshall to write a piece on the Zippies; the cover story broke records for being one of the most publicized stories of the year and was used to promote Wired's HotWired news service. HotWired spawned websites Webmonkey, the search engine HotBot, a weblog, Suck.com. In June 1998, the magazine launched a stock index, the Wired Index, called the Wired 40 since July 2003.
The fortune of the magazine and allied enterprises corresponded to that of the dot-com bubble. In 1996, Rossetto and the other participants in Wired Ventures attempted to take the company public with an IPO; the initial attempt had to be withdraw
FidoNet is a worldwide computer network, used for communication between bulletin board systems. It uses a store-and-forward system to exchange private and public messages between the BBSes in the network, as well as other files and protocols in some cases; the FidoNet system was based on a number of small interacting programs. Only one of these interacted with the BBS system directly and was the only portion that had to be ported to support other BBS software; this eased porting, FidoNet was one of the few networks, supported by all BBS software, as well as a number of non-BBS online services. This modular construction allowed FidoNet to upgrade to new data compression systems, important in an era using modem-based communications over telephone links with high long-distance calling charges; the rapid improvement in modem speeds during the early 1990s, combined with the rapid decrease in price of computer systems and storage, made BBSes popular. By the mid-1990s there were 40,000 FidoNet systems in operation, it was possible to communicate with millions of users around the world.
Only UUCPNET came close in terms of breadth or numbers. The broad availability of low-cost Internet connections starting in the mid-1990s lessened the need for FidoNet's store-and-forward system, as any system in the world could be reached for equal cost. Direct dialing into local BBS systems declined. Although FidoNet had shrunk since the late 1990s, it has remained in use today despite internet connectivity becoming universally available. There are two major accounts of the development of the FidoNet, differing only in small details. Around Christmas 1983, Tom Jennings started work on a new MS-DOS–hosted bulletin board system that would emerge as Fido BBS. Jennings set up the system in San Francisco some time in early 1984. Another early user was John Madil, trying to set up a similar system in Baltimore on his Rainbow 100. Fido started spreading to new systems, Jennings started keeping an informal list of their phone numbers, with Jennings becoming #1 and Madil #2. Jennings released the first version of the FidoNet software in June 1984.
In early 1985 he wrote a document explaining the operations of the FidoNet, along with a short portion on the history of the system. In this version, FidoNet was developed as a way to exchange mail between the first two Fido BBS systems, Jennings' and Madil's, to "see if it could be done for the fun of it"; this was first supported in Fido V7, "sometime in June 84 or so". In early 1984, Ben Baker was planning on starting a BBS for the newly forming computer club at the McDonnell Douglas automotive division in St. Louis. Baker was part of the CP/M special interest group within the club, he intended to use the seminal, CP/M-hosted, CBBS system, went looking for a machine to run it on. The club's president told Baker that DEC would be giving them a Rainbow 100 computer on indefinite loan, so he made plans to move the CBBS onto this machine; the Rainbow contained two processors, an Intel 8088 and a Zilog Z80, allowing it to run both MS-DOS and CP/M, with the BBS running on the latter. When the machine arrived, they learned that the Z80 side had no access to the I/O ports, so CBBS could not communicate with a modem.
While searching for software that would run on the MS-DOS side of the system, Baker learned of Fido through Madil. The Fido software required changes to the serial drivers to work properly on the Rainbow. A porting effort started, involving Jennings and Baker; this caused all involved to rack up considerable long distance charges as they all called each other during development, or called into each other's BBSes to leave email. During one such call "in May or early June", Baker and Jennings discussed how great it would be if the BBS systems could call each other automatically, exchanging mail and files between them; this would allow them to compose mail on their local machines, deliver it as opposed to calling in and typing the message in while on a long-distance telephone connection. Jennings responded by calling into Baker's system that night and uploading a new version of the software consisting of three files: FIDO_DECV6, FIDONET, NODELIST. BBS; the new version of FIDO BBS had a timer that caused it to exit at a specified time at night, as it exited it would run the separate FIDONET program.
NODELIST was the list of Fido BBS systems, which Jennings had been compiling. The FIDONET program was what became known as a mailer. FIDO was modified to use a unused numeric field in the message headers to store a node number for the machine the message should be delivered to; when FIDONET ran, it would search through the email database for any messages with a number in this field. FIDONET collected all of the messages for a particular node number into a file known as a message packet. After all the packets were generated, one for each node, the FIDONET program would look up the destination node's phone number in NODELIST. BBS, call the remote system. Provided that FIDONET was running on that system, the two systems would handshake and, if this succeeded, the calling system would upload its packet, download a return packet if there was one, disconnect. FIDONET would unpack the return packet, place the received messages into the local system's storage, move onto the next packet; when there were no remaining packet, it would exit, run the FIDO BBS program.
In order to lower long distance charges, the mail exchanges were timed to run late at night 4 AM. This would be known as national mail hour, still
Electronic mail is a method of exchanging messages between people using electronic devices. Invented by Ray Tomlinson, email first entered limited use in the 1960s and by the mid-1970s had taken the form now recognized as email. Email operates across computer networks, which today is the Internet; some early email systems required the author and the recipient to both be online at the same time, in common with instant messaging. Today's email systems are based on a store-and-forward model. Email servers accept, forward and store messages. Neither the users nor their computers are required to be online simultaneously. An ASCII text-only communications medium, Internet email was extended by Multipurpose Internet Mail Extensions to carry text in other character sets and multimedia content attachments. International email, with internationalized email addresses using UTF-8, has been standardized, but as of 2017 it has not been adopted; the history of modern Internet email services reaches back to the early ARPANET, with standards for encoding email messages published as early as 1973.
An email message sent in the early 1970s looks similar to a basic email sent today. Email had an important role in creating the Internet, the conversion from ARPANET to the Internet in the early 1980s produced the core of the current services; the term electronic mail was used generically for any electronic document transmission. For example, several writers in the early 1970s used the term to describe fax document transmission; as a result, it is difficult to find the first citation for the use of the term with the more specific meaning it has today. Electronic mail has been most called email or e-mail since around 1993, but variations of the spelling have been used: email is the most common form used online, is required by IETF Requests for Comments and working groups and by style guides; this spelling appears in most dictionaries. E-mail is the format that sometimes appears in edited, published American English and British English writing as reflected in the Corpus of Contemporary American English data, but is falling out of favor in some style guides.
Mail was the form used in the original protocol standard, RFC 524. The service is referred to as mail, a single piece of electronic mail is called a message. EMail is a traditional form, used in RFCs for the "Author's Address" and is expressly required "for historical reasons". E-mail is sometimes used, capitalizing the initial E as in similar abbreviations like E-piano, E-guitar, A-bomb, H-bomb. An Internet e-mail consists of an content. Computer-based mail and messaging became possible with the advent of time-sharing computers in the early 1960s, informal methods of using shared files to pass messages were soon expanded into the first mail systems. Most developers of early mainframes and minicomputers developed similar, but incompatible, mail applications. Over time, a complex web of gateways and routing systems linked many of them. Many US universities were part of the ARPANET, which aimed at software portability between its systems; that portability helped make the Simple Mail Transfer Protocol influential.
For a time in the late 1980s and early 1990s, it seemed that either a proprietary commercial system or the X.400 email system, part of the Government Open Systems Interconnection Profile, would predominate. However, once the final restrictions on carrying commercial traffic over the Internet ended in 1995, a combination of factors made the current Internet suite of SMTP, POP3 and IMAP email protocols the standard; the diagram to the right shows a typical sequence of events that takes place when sender Alice transmits a message using a mail user agent addressed to the email address of the recipient. The MUA formats the message in email format and uses the submission protocol, a profile of the Simple Mail Transfer Protocol, to send the message content to the local mail submission agent, in this case smtp.a.org. The MSA determines the destination address provided in the SMTP protocol, in this case firstname.lastname@example.org, a qualified domain address. The part before the @ sign is the local part of the address the username of the recipient, the part after the @ sign is a domain name.
The MSA resolves a domain name to determine the qualified domain name of the mail server in the Domain Name System. The DNS server for the domain b.org responds with any MX records listing the mail exchange servers for that domain, in this case mx.b.org, a message transfer agent server run by the recipient's ISP. smtp.a.org sends the message to mx.b.org using SMTP. This server may need to forward the message to other MTAs before the message reaches the final message delivery agent; the MDA delivers it to the mailbox of user bob. Bob's MUA picks up the message using either the Post Office Protocol or the Internet Message Access Protocol. In addition to this example and complications exist in the email system: Alice or Bob may use a client connected to a corporate email system, such as IBM Lotus Notes or Microsoft Exchange; these systems have their own internal email format and their clients communicate with the email server using a vendor-specific, proprietary protocol. The server sends or receives email via the Internet through the product's Internet mail gateway which does any necessary reformatt