Christmas is my favorite holiday and it's observed as both a religious and cultural holiday by billions of people on earth!  
What are the origins of Christmas?
Traditionally, it is based on the birth of Jesus in Bethlehem, frequently referred to as the Nativity.
What is the Nativity?  
For Christians, the Nativity is the term for Jesus's birth and the achievement of God's promise to save the world from sin. Have you heard of decorative Nativity scenes?
No, not at all.  What is that?
They are the recreations of Jesus's birth including Mary and Joseph, and can be in the form of models or acted out with humans portraying the family. 
That is incredibly interesting.  I know that many churches will place Nativity scenes outside their buildings during the season.  
I see that a lot. I like other Christmas traditions such as putting up Christmas trees, handing out candy canes, and hanging up stockings.