3100 BC Writing in Mesopotamia
Writing is developed, at Sumer, as cuneiform script on clay tablets

3100 BC Egyptians write in hieroglyphs
The Egyptian hieroglyphic script develops at much the same time as the Sumerian cuneiform

3100 BC
The invention of writing marks the transition, in academic terms, from prehistory to history

2500 BC Indus seals a mystery
The delicate seals of the Indus civilization are in a script as yet undeciphered

1500 BC Bamboo books
The Chinese develop a form of scroll, made of strips of bamboo threaded together and rolled up like a wooden blind

768 Empress of Japan has a million charms
The empress of Japan, in a remarkable start to the story of printing, commissions a million copies of a Buddhist charm

868 Earliest surviving printed book
The world's first known printed book, a Diamond Sutra, is commissioned by a Buddhist monk in honour of his parents

1050 Movable type in China
The concept of movable type for printing is pioneered in China, using fired clay, but it proves impractical

1050 Pigeon post in Baghdad
The rulers of Baghdad harness homing pigeons as postmen.

1077 Penitence at Canossa
The emperor Henry IV stands as a penitent outside the pope's castle at Canossa, so as to be released from excommunication.

1380 Movable type in Korea
Koreans establish the first type foundry, casting movable type in bronze

1456 Movable type in Germany
A copy of Europe's first book printed from movable type, the Gutenberg Bible, is completed in Mainz

1653 Flags to signal at sea
The English admiral Robert Blake introduces a system of signalling at sea by means of flags

1809 Another pope imprisoned by Napoleon
Napoleon, in response to his excommunication, has pope Pius VII arrested and kept in captivity in northern Italy and then France

1838 Morse's electric telegraph
US inventor Samuel Morse gives the first public demonstration, in Philadelphia, of his electric telegraph

1840 Penny Black
Rowland Hill introduces in Britain the world's first postage stamps - the Penny Black and Two Pence Blue

1844 World's first telegraph line
Samuel Morse and his assistant Alfred Vail complete the first telegraph line, between New York and Baltimore

1858 First Atlantic cable
US entrepreneur Cyrus W. Field succeeds in laying a telegraph cable across the Atlantic, but it fails after only a month

1870 Telegraph across Australia
Adelaide and Darwin are linked across the entire Australian continent by the Overland Telegraph Line

1871 Meucci files telephone patent
Italian US immigrant Antonio Meucci files a patent in New York for the invention of the telephone

1876 'Mr Watson, come here. I want to see you.'
Alexander Graham Bell makes the first practical use of his telephone, summoning his assistant from another room with the words 'Mr Watson, come here. I want to see you.'

1876 Bell goes public with telephone
Alexander Graham Bell demonstrates his new invention, the telephone, at the US Centennial Exhibition in Philadelphia

1895 Marconi transmits radio signal
21-year-old Guglielmo Marconi succeeds in transmitting a radio signal more than a mile at his home near Bologna

1896 Marconi patents radio
22-year-old Guglielmo Marconi takes out a patent in Britain for the invention of radio

1899 Wireless across English Channel
Italian inventor Guglielmo Marconi succeeds in transmitting a wireless telegraph message across the English Channel

1899 Radio sensation from ships at sea
Marconi equips two ships to send radio reports to New York on the progress of the yachts racing for the America's Cup

1901 Radio across the Atlantic
Guglielmo Marconi transmits a radio message in Morse code 2100 miles, from Poldhu in Cornwall to St John's in Newfoundland

1907 Radio receiver patented
US inventor Lee De Forest patents the Audion, a sensitive vacuum-tube radio receiver

1910 Caruso broadcasts from the Met
Lee De Forest broadcasts Enrico Caruso live from the Metropolitan Opera House in New York, but with mixed success owing to the poor quality

1910 Crippen arrested on ocean liner
Telegraph messages lead to the arrest of Dr Crippen and his mistress Ethel Le Neve in mid-Atlantic

1913 Radio time signals
The US navy begins transmitting by radio a regular time signal, much used by the nation's watchmakers and menders.

1915 First trans-American telephone call
Alexander Graham Bell again summons his assistant Thomas Watson (as in 1876), but this time he is in New York and Watson in San Francisco

1915 Radiotelephone message across Atlantic
Radiotelephone messages are transmitted from Arlington in Virginia to the Eiffel Tower in Paris

1926 Baird demonstrates television
John Logie Baird gives the world's first demonstration of television to a group assembled in his attic rooms in London

1929 BBC launches TV
The British Broadcasting Corporation uses Logie Baird's system for its first trial TV broadcasts

1965 Early Bird satellite
The first communications satellite, Early Bird, is launched from Cape Carnaveral

1965 Pope and Patriarch revoke excommunications
Pope Paul VI and Patriarch Athenagoras preside over simultaneous ceremonies, in Rome and Istanbul, revoking the mutual excommunications of 1054

1976 Apple computer
Steve Wozniak and Steve Jobs design and market a personal computer, calling it the Apple

1983 MIDI becomes electronic standard
The US system MIDI (Musical Instrument Digital Interface) becomes the industry standard for electronic communication in music

1989 Internet experiment by Berners-Lee
At CERN, in Geneva, Tim Berners-Lee and Robert Cailliau build ENQUIRE, a first step towards the future World Wide Web

1990 World Wide Web
Tim Berners-Lee, working at CERN in Geneva, publishes the first formal proposal for the World Wide Web

1991 First website
Tim Berners-Lee, using CERN computers, puts online the first website at http://info.cern.ch

1997 Birth of Google
Larry Page and Sergey Brin, both Ph.D. students at Stanford University, register the domain name google.com

2001 Wikipedia
Wikipedia, the 'Free Encyclopedia', is put online by Jimmy Wales as an empty shell which members of the public are invited to fill with content

2006 Google buys YouTube
Google pays $1.65 billion for the website YouTube, launched less than two years previously

2007 Apple's iPhone arrives
Apple's iPhone goes on sale in the USA and 270,000 are sold in the first thirty hours

2010  July 25
The website Wikileaks publlishes more than 90,000 classified internal reports about US involvement in Afghanistan since 2004

2010  November 28
Wikileaks publishes another batch of US government documents, this time diplomatic cables of which about 100,000 are maked 'secret' or 'confidential'