What is Remembrance Day?
The second Sunday of November is Remembrance Sunday, but what does it all mean and what are you meant to do?
At 11am men, women and children all across Britain hold a two minute silence to remember the millions who have died in war.
The silence is usually observed at war memorials, cenotaphs, religious services and shopping centres throughout the country.
The Royal Family, along with top politicians and religious leaders, gather at The Cenotaph in Whitehall, London, for a service.
What is Armistice Day?
Armistice Day is on 11 November. It's also known as Remembrance Day.
A two minute silence is observed at 11am on the 11th day of the 11th month because this is when World War I, or the Great War, ended in 1918.
But now, this anniversary is used to remember all the people who've died in wars since World War I.
This includes World War II, the Falklands War, the Gulf War, and conflicts in Afghanistan and Iraq.
Why do we hold a two minute silence?
The first two minute silence in Britain was held on 11 November 1919, when King George V asked the public to observe a silence at 11am.
This was one year after the end of World War I.
He made the request so "the thoughts of everyone may be concentrated on reverent remembrance of the glorious dead".