Armistice Day is on 11 November and is also known as Remembrance Day.
It marks the day World War One ended, at 11am on the 11th day of the 11th month, back in 1918.
Nowadays, people remember those who were lost in the war by holding a two-minute silence and by wearing a red poppy.
We spoke to some of you to find out what Remembrance Day is and why it's so important. Some of you even told us some of your Remembrance Day stories.