It was declared as a national holiday in many allied nations, to commemorate the fallen. After World War II, the name was changed to Remembrance Day here in the UK, and Veterans Day in the US. Many people still call it Armistice Day, myself included. It seems interchangeable with Remembrance day.We wear the red poppy as an outward show of our remembrance, the use was inspire by the WWI poem "In Flanders Fields". It's opening lines refer to the many poppies that were the first flowers to grow in the churned earth of the soilders graves in Flanders.
One of my favourite war poems, to commemorate the dead is "For The Fallen", by Laurence Binyon. It is one of his best known, as the fourth stanza adorns numerous memorials;
"They shall not grow old, as we that left grow old:
Age shall not weary them, nor the years contemn.
At the going down of the sun, and in the morning
We will remember them"
So I hope, that today, the 11/11, you will take a moment to just remember the men that lay down their lives during the wars, so that we could live in the countries we do.