why do we say xmas instead of christmas

Christmas has evolved into a complicated holiday with multiple layers of meaning. It started out as a religious celebration for the birth of Jesus Christ, but over the centuries it has also become a cultural and commercial holiday. So the term "Xmas" is often used to emphasize the non-religious aspects of the holiday, such as gift-giving and family gatherings. It's a shortened form of "Christ" that highlights the secular aspects of the holiday.