Ray Tomlinson, the inventor of email and the use of @ on computers, has died aged 74.
An electrical engineer and computer programmer, Tomlinson devised 'elecltronic mail' on the precursor to the internet, the ARPANET (Advanced Research Projects Agency Network).
Here are just five ways his main creation has revolutionised our lives:
1) A steady decline in the numbers of letters
There has been a 47 per cent reduction in letters sent via the US Postal Service between 1990 and 2014 - from 268 billion letters a year to 141 billion letters.
In 2010, letters sent through the Royal Mail in the UK had fallen to 68 million, the lowest level in 15 years - Telegraph reported.
2) The introduction of @ into our lives
Previously used in accounting to represent "at the rate of", Tomlinson co-opted the @ as the link between the user name and the host domain.
Since this 1971 innovation - the @ has become the short form of at in various forms of electronic communication, such a Twitter and texts.
3) Instant messaging
Email led the way to easier and more accessible forms of non-verbal communication such as MSN Messenger, WhatsApp and Snapchat.
Films such as "You've Got Mail" show how email and instant messaging were intrinsically linked early on in the email revolution.
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Most millenials spent their teenage years using forums including MSN Messenger to chat to friends and (attempt to) develop romantic prospects.
4) Working from home
With the use of a telephone and an email account, millions of people have been able give up the commute to work from the kitchen table.
By 2014, 4.2 million UK workers (13.9 per cent of the workforce) work from home - BBC reports.
This figure includes those who nominally work from home but spend the majority of their time visiting clients elsewhere.
5) No escape from work
The rise of the work phone and the 24-hour nature of email means employees can be reached at all hours by managers and clients.
In 2013, the German Ministry of Labour felt forced to ban managers from emailing and calling subordinates out of hours to prevent them burning out.Reuse content