2016 was the leap year that began on Friday and was a Gregorian calendar year. Here are some key events and facts about 2016:

1. The Summer Olympics were held in Rio de Janeiro, Brazil.

2. Donald Trump was elected as the 45th President of the United States.

3. Brexit - The United Kingdom voted to leave the European Union in a national referendum.

4. The Chicago Cubs won the World Series, their first championship in 108 years.

5. David Bowie and Prince died within months of each other.

6. NASA's Juno spacecraft entered Jupiter's orbit.

7. The Panama Papers leak revealed large-scale tax evasion by world leaders and celebrities.

8. The Disney movie "Moana" was released.

9. Pokemon Go became a global phenomenon.

10. The US presidential election featured Hillary Clinton and Donald Trump as the main candidates.

11. Lionel Messi announced his retirement from international football after Argentina lost the Copa America final.

12. Britain's Andy Murray became the first British man since Fred Perry in 1936 to win the Wimbledon singles title.

These are just some of the notable events from 2016. It was a significant year with many important developments in politics, sports, entertainment, and technology.