2011 was an extraordinary year. And the Guardian was at the very heart of it. It was a year that will be remembered for the phone hacking scandal, uncovered only by the persistence and skill of Guardian investigative reporter Nick Davies, and the seismic changes it forced in the relationship between parliament, the media and the police. It was a year that will be remembered because a Guardian reporter was passed a memory stick, small enough to hang on a key ring, but which contained 250.000 US diplomatic cables whose publication provoked reverberations around the world. And it was a year packed with drama, tragedy and inspiration: the Arab spring; the tsunami in Japan; the August riots; the killing of Bin Laden, the capture of Mladic, and a royal wedding.The year's events are vividly documented and debated here by writers including David Leigh, Nick Davies, Marina Hyde, Polly Toynbee, Hadley Freeman, Simon Jenkins and Jonathan Freedland. George Monbiot explains why the Fukushima nuclear disaster affirmed his faith in atomic energy, Charlie Brooker brilliantly satirises the case of a Twitter user convicted over a joke, and Margaret Drabble lambasts the coalition's plans for the NHS. Richard Williams celebrates the life of Seve Ballesteros, Declan Walsh reveals the truth about Osama bin Laden's last hours, and Jack Shenker reports on being caught in a roundup by Egypt's notorious security services just before the fall of Hosni Mubarak - in a revolution documented here by Ahdaf Soueif from Tahrir Square.Away from the big news stories, Decca Aitkenhead reveals another side of Ann Widdecombe, poet Simon Armitage has a difficult encounter with his musical hero Morrissey, and Steve Bell looks back over 30 years of cartooning for the Guardian. Martin Kettle contemplates whether MI5 were right to spy on his father, and regular Guardian correspondent David Hockney dashes off another iPad-composed letter to the paper - this time not about smoking.