Raymond Samuel Tomlinson (April 23, 1941 – March 5, 2016) was an American[1][2][3][4] programmer who invented the firstemail program on theARPANET system, the precursor to the Internet, in 1971;[5][6][7][8] it was the first system able to send mail between users on different hosts connected to ARPANET. Previously, mail could be sent only to others who used the same computer. To achieve this, he used the@ sign to separate theusername from the name of their machine, a scheme which has been used in email addresses ever since.[9]
TheInternet Hall of Fame in its account of his work commented "Tomlinson's email program brought about a complete revolution, fundamentally changing the way people communicate."[10][11] He is credited with the invention of theTCP three-way handshake[12] which underliesHTTP and many other keyInternet protocols.
Tomlinson was born[13] inAmsterdam, New York, but his family soon moved to the small, unincorporated village ofVail Mills,Broadalbin, New York.[14][15] His father Raymond Tomlinson worked in carpet mills and later worked in the grocery business. His mother Dorothy Tomlinson worked for a dry cleaner.[16] He attended Broadalbin Central School in nearby Broadalbin, New York.[17] Later he attendedRensselaer Polytechnic Institute (RPI) inTroy, New York, where he participated in the co-op program withIBM. He received a bachelor's degree inelectrical engineering from RPI in 1963.[18]
After graduating from RPI, he entered theMassachusetts Institute of Technology (MIT) to continue his electrical engineering education. At MIT, Tomlinson worked in the Speech Communication Group, focusing onspeech synthesis. He became interested in computers after seeing students playSpacewar!.[19] Enthralled by the video game, he spent more time working with digital systems and integrated them into his thesis project. He developed an analog–digital hybrid speech synthesizer as the subject of his thesis for the master's degree in electrical engineering, which he received in 1965.[14]
In 1967, he joined the technology company of Bolt, Beranek and Newman (BBN; nowRaytheon BBN), where he helped develop theTENEX operating system including theARPANETNetwork Control Program, implementations ofTelnet, and implementations on the self-replicating programsCreeper and Reaper.
Tomlinson also developed CPYNET, a file transfer program designed to transmit files between computers connected to the ARPANET. In 1971, he was asked to adapt an existing program calledSNDMSG—which allowed users to leave messages for others on the sametime-sharing computer—so that it could run on TENEX.[20] He incorporatedsource code from CPYNET into SNDMSG, enabling users to send messages to others ondifferent computers over the network. This innovation marked the creation of the first networked email system.[21]
The first email Tomlinson sent was a test message between two computers placed side by side.[22] The content of the message was not preserved, and Tomlinson later described it as insignificant, likely consisting of a random string such as "QWERTYUIOP." This is often misquoted as "The first e-mail was QWERTYUIOP."[23] He later stated, "The test messages were entirely forgettable and I have, therefore, forgotten them."[24]
To distinguish destination addresses from local usernames, Tomlinson selected the@ symbol to indicate the recipient's location (user@host), a format that remains standard inemail addressing. The symbol was chosen because it was not used in usernames or in TENEX programming, and it intuitively conveyed the intended meaning.[13][14][25] The @ sign, which was relatively obscure at the time, was added to theMuseum of Modern Art's architecture and design collection in 2010, credited to Tomlinson and described as a "defining symbol of the computer age."[13][14][25][26]
Initially, the email messaging system was not considered significant. Its development was not directed by his employer, and Tomlinson pursued the idea independently, stating that it "seemed like a neat idea."[14] Upon demonstrating the system to a colleague, he remarked, "Don't tell anyone! This isn't what we're supposed to be working on."[27] Despite its informal origins, the system quickly gained popularity within the ARPANET research community and became one of the network's most enduring applications.[13] Tomlinson later remarked that he was not particularly surprised by the eventual widespread use of email, stating, "I see email being used, by and large, exactly the way I envisioned."[28]
Tomlinson said he preferred "email" over "e-mail," joking in a 2010 interview that "I'm simply trying to conserve the world's supply of hyphens" and that "the term has been in use long enough to drop the hyphen."[29]
Tomlinson remained at BBN for the rest of his career, serving as a principal scientist.[22] In his personal life, he maintained a minimal relationship with consumer technology.Adrienne LaFrance ofThe Atlantic described him as a "self-professed Luddite," noting that he did not own a mobile phone and had only recently created aFacebook account.[30]
Tomlinson died of aheart attack on March 5, 2016, at his home inLincoln, Massachusetts, at the age of 74.[18][14] News of his death drew attention and tributes from the technology community, including a message fromVint Cerf,[31] co-developer of theTCP/IP protocol and a founding architect of the Internet.
In 2022, Email Day, an annual, national holiday was established in honor of Ray Tomlinson and his creation of email. April 23 (Tomlinson's birthday) was chosen.[35]
^Tomlinson, Ray (June 5, 2009)."Oral History of Raymond (Ray) Tomlinson"(PDF) (Interview). Interviewed by Weber, Marc; Hendrie, Gardner. Cambridge, Massachusetts: Computer History Museum. pp. 2–3. RetrievedApril 7, 2025.
