The following were some of the top news stories in the United States during 2012.
Trayvon Martin shooting. Martin, an unarmed black teenager was shot dead in Florida by neighborhood watch patrol volunteer George Zimmerman. Zimmerman said he shot Martin in self defense during a struggle, but will stand trial next June for murder.
Whitney Houston, among the top singers of the 1980s and 1990s, died at age 48.
Deadly Midwest tornadoes. A spate of tornadoes and thunderstorms tore across the South and Midwest, killing dozens of people and injuring hundreds of others.
The killer storms were followed by devastating spring and summer wildfires in the West that claimed several lives, torched hundreds of homes and forced the evacuation of thousands of residents.
Dick Clark, whose long-running television dance show "American Bandstand" helped rock 'n' roll win acceptance in mainstream America, died at age 82.
Gay marriage. President Barack Obama became the first sitting president to say same-sex couples should be allowed to wed. In the November election, Maine, Maryland and Washington approved same-sex marriage by popular vote. In December, the U.S. Supreme Court agreed to review two key same-sex marriage cases.
Facebook IPO. The historic initial public offering of Facebook Inc did not go as planned, due to an overly optimistic valuation and trading glitches. The stock fell to less than half of its IPO value in three months, and the offering became the subject of numerous lawsuits.
Penn State. Jerry Sandusky, 68, Penn State University's former defensive coordinator, was convicted of 45 counts of sexually abusing 10 boys over 15 years. He was sentenced to 30 to 60 years in prison. The scandal sparked a national debate over child sex abuse, embarrassed the university and implicated a number of its top officials including legendary football head coach, the late Joe Paterno.
Supreme Court Healthcare law ruling. A sharply divided U.S. Supreme Court upheld the centerpiece of President Obama's signature healthcare overhaul law that requires that most Americans get insurance by 2014 or pay a financial penalty. The vote was 5-4.
Niagara Falls crossing. Aerialist Nik Wallenda made a historic tightrope crossing over Niagara Falls, stepping onto safe ground in Canada to wild cheers after completing his journey through wind and mist on a 2-inch (5-cm) diameter cable.
Rodney King, whose videotaped beating made him a symbol of police brutality and led to racially charged riots in Los Angeles, died at the age of 47.
Mass shooting in Aurora, Colorado. A gunman opened fire during a midnight screening of the Batman movie "The Dark Knight Rises" in suburban Denver, killing 12 people and wounding 58 others. Police identified former neuroscience graduate student James Holmes as the suspect in a crime that renewed debate about the sale of powerful semi-automatic rifles and extended capacity magazines.
Shooting at Wisconsin Sikh temple. A gunman killed six people and critically wounded three others at a Sikh temple before police shot him dead.
Empire State Building shooting. An out-of-work fashion designer fatally shot a former co-worker near the Empire State Building and was then killed in a blaze of gunshots by police, stunning tourists and commuters outside of one of New York's most popular landmarks.
U.S. astronaut Neil Armstrong, who took a giant leap for mankind when he became the first person to walk on the moon, died at the age of 82.
Benghazi attack. Militants stormed the U.S. mission in Benghazi, Libya, on the anniversary of the September 11, 2001, attacks on New York and Washington, killing U.S. Ambassador Christopher Stevens and three other Americans.
The attack - the first to kill a U.S. ambassador in the line of duty since 1979 - sparked criticism of the Obama administration. An official inquiry found widespread failures in both security planning and internal management.
Superstorm Sandy. More than 130 people were killed when Hurricane Sandy pummeled the east coast of the United States. Thousands more were left homeless as the storm tore through areas of New York, New Jersey and Connecticut, causing an estimated $50 billion in damage.
Lance Armstrong. Disgraced cycling champion Armstrong had his seven Tour de France victories scratched from the records and was banned from cycling for life after the International Cycling Union (UCI) ratified the United States Anti-Doping Agency's (USADA) sanctions against him. A USADA report said Armstrong had been involved in the "most sophisticated, professionalized and successful doping program that sport has ever seen."
Record-setting skydiver. Austrian daredevil Felix Baumgartner leapt into the stratosphere from a balloon near the edge of space 24 miles above Earth and safely landed, setting a record for the highest skydive and breaking the sound barrier in the process.
U.S. general election. Democratic U.S. President Obama beat Republican rival Mitt Romney to win a second term in the White House. Obama's reelection was clinched with the votes of minority Hispanic and black voters, marking a shift in electoral demographics.
Resignation of CIA Director. David Petraeus, the head of the spy agency and warrior-scholer who played a key role in the Iraq war, led the U.S. Central Command and commanded U.S. and NATO troops in Afghanistan, stepped down after admitting he had engaged in an extramarital affair.
Sandy Hook Elementary School shooting. Adam Lanza shot dead 20 children and six staff members at the school in Newtown, Connecticut, before killing himself. He also killed his mother. The mass shooting once again prompted vigorous debate on gun laws.
(Sources: Reuters; Pew Research Center for the People & the Press)