Who invented email?

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Chennai: Shiva Ayyadurai, who claimed he developed e-mail even as a teenaged student in America, arrived Wednesday for a warm hug from octogenarian father at home in Chennai.
Siva had gone to the U.S. for schooling and claimed he had developed a computer programme when hardly 14, named it EMAIL and got the US patent for it five years later in 1982.
Friends hail him as ‘Email Tamizhan’, though his claims as the developer of e-mail have been stoutly contested.
Siva, now 49, will receive honorary doctorate from the Vinayaka Mission University at Salem on  July 7, “for doing us Tamils proud as the inventor of e-mail when he was still in his teens”, according to the university’s joint registrar B Dhanasekarran.
After this honour, Shiva plans to tour Tiruvannamalai, Coimbatore and a few other places for sharing his academic and research experiences with students.
Shiva teaches systems visualization at the Massachusetts Institute of Technology (MIT) Siva’s latest facebook post reads, “The greatest sin of the Tamil people is they don't even know their own greatness”. There are some e-posts disputing Shiva’s claim as the inventor of e-mail.
One of them, found on the Special Interest Group Computers, Information and Society website, has Thomas Haigh, a historian of information technology  writing, "Ayyadurai is, to the best of my knowledge, the only person to have claimed for him or herself the title 'inventor of email.”
Haigh argued that while EMAIL was impressive for a teenager's work, it contained no features that were not present on previous electronic mail systems and had no obvious influence on later systems.
"The most striking thing about Ayyadurai’s claim to have invented electronic mail is how late it comes. Somehow it took him thirty years to alert the world to [his] greatest achievement."However, Ayyadurai had a famous supporter in his undergraduate professor Noam Chomsky of MIT, who accused Ayyadurai's detractors of displaying "the childish tantrums of industry insiders."
One theory is that computer engineer Ray Tomlinson had invented the internet based email in late 1971.