I like the holidays.  I particularly like Christmas. How about you? 
Yes me and billions across the world celebrate this special holiday!
How did the Christmas holiday start? 
It is based on the Christian narrative of the birth of Jesus in Bethlehem.
When did Christmas become a 25 December celebration? 
Jesus's exact birth is unknown but by the 4th century the church had placed Christmas on Dec 25.
When did it become so commercialized? 
Really only over the past century or so did the exchanging of present become a major tradition.