The House Judiciary Committee takes the first steps in the process of impeaching President Nixon, citing obstruction of justice

Faced by the prospect of impeachment over Watergate, President Nixon resigns

Richard Nixon is succeeded as US president by his vice-president, Gerald Ford

President Ford pardons ex-president Nixon for his part in the Watergate affair, thus removing the possibility of criminal charges

Muhammad Ali regains the world heavyweight title, beating George Foreman in Zaire in a fight that becomes known as the Rumble in the Jungle

US author E.L. Doctorow sets his novel Ragtime in the early years of the 20th century

Milos Forman directs Jack Nicholson in One Flew Over the Cuckoo's Nest, based on a novel by Ken Kesey

US director Steven Spielberg has a major success with his second feature film, Jaws

School friends Bill Gates and Paul Allen found a software firm, calling it Microsoft

Mikhail Baryshnikov dances in the New York premiere of Twyla Tharp's ballet Push Comes to Shove

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

14-year-old Jodie Foster stars as a drug-addicted child prostitute in Martin Scorsese's Taxi Driver

The landing section of the US spacecraft Viking 1 detaches from the orbiter and makes a successful landing on Mars

Black American author Alex Haley traces his family origins in Africa in Roots

333 days after leaving Earth, the landing section of the US spacecraft Viking 2 touches down on Mars and begins sending back photographs

Bulgarian-born US artist Christo (Christo Javacheff) constructs a 24-mile Running Fence in California

The incumbent president Gerald Ford is defeated by Democrat Jimmy Carter in the US election

Steven Spielberg writes and directs an inflential science fiction movie, Close Encounters of the Third Kind

George Lucas writes and directs a science fantasy, Star Wars, launching a narrative that will be expanded in a further five films

Elvis Presley dies, aged 42, at his home in Memphis, Tennessee

After making several films together, Woody Allen and his partner Diane Keaton have an Oscar-winning success with Annie Hall

US author John Irving has wide success with his novel The World According to Garp

Muhammad Ali is the first boxer to become world heavyweight champion three times, defeating Leon Spinks in a return match a year after losing the title

Francis Ford Coppola directs Marlon Brando and Martin Sheen in Apocalypse Now

Partial meltdown of a US nuclear power station at Three Mile Island, near Harrisburg, spreads radioactive steam over a large surrounding area