Today is Veterans Day in the US and Remembrance Day in Canada and Europe. Poppies are used to symbolize the trench warfare of World War I. In the UK most people wear artificial poppies on their lapels.
Why November 11? Here’s what I wrote last year:
Veterans Day marks the anniversary of the coming into effect of the Armistice during WWI (technically an armistice is a cease-fire so the war did not end until the signing of the peace treaty at the Paris Peace Conference in June 1919, but most people disregard this and count the war as lasting from 1914-18).
The Armistice came into effect (on purpose) on the eleventh hour, of the eleventh day or the eleventh month, but had actually been agreed earlier that morning around 6am in the Compiègne Forest, just north of Paris. It was signed by General Foch for the Allies and a guy called Matthias Erzberger for the Germans at a special railroad siding in the forest.
The very same siding was used decades later for the signing of the armistice in World War II.