This weekend marks Remembrance Sunday, when people across the UK honour those who have lost their lives in war.
Millions of red poppies are sold each year in the build-up to the day to commemorate the war dead, while the nation will fall silent at 11am in tribute.
Remembrance Sunday is always held on the second Sunday in November, while Armistice Day is always held on the eleventh day of the eleventh month to commemorate the signing of the armistice.
Here is everything you need to know.
What is Remembrance Day?
A two-minute silence is held at 11am on November 11, which marks the day the armistice was signed between the Allies and Germany that brought the end of WW1.
It was a tradition first started by King George V in 1919, and initially called Armistice Day.
The armistice took place on the eleventh hour of the eleventh day of the eleventh month in 1918, which is why the UK holds two minutes of silence at 11am every November 11.
It was signed in Compiegne in Northern France and forced Germans to evacuate invaded countries within a two-week period.
However, after the outbreak of WW2, many countries changed the name of this day, with some members of the Commonwealth choosing to call it Remembrance Day. In the UK, it is now known as both.
In the UK, Remembrance Sunday is held on the Sunday nearest to Armistice Day and marked by ceremonies at war memorial across the country.
A National Service of Remembrance, which is attended by members of the Royal Family, the Government and representatives from the armed forces, is held at 11am at The Cenotaph in Whitehall.
The Royal Marine buglers signal the start of the silence by playing The Last Post and The Rouse, and it is ended by a gun salute by the Royal Horse Artillery.
When is Armistice Day and Remembrance Sunday?
This year, Armistice Day and Remembrance Sunday falls on Sunday, November 10.
Armistice Day is on Monday, November 11.
What time is the two-minute silence?
The two minute silence will be held at 11am on Sunday and Monday.
In the lead-up to Remembrance Day, you will see veterans all over the country selling poppies.
The reason the poppies are worn is because they are the flowers which grew on the battlefields after WW1 ended.
The Royal British Legion is the charity which runs the poppy appeal each year and it gives the money to the service women and men who are still alive and whose lives have been changed by war.
This year will see thousands of people opting for white poppies over the traditional red.
The Remembrance Sunday Cenotaph Service takes place at 11am on Sunday, November 11.
For Remembrance Day events in your area, visit the British Legion.