Christmas has always been one of the most celebrated holidays in Hong Kong, especially since the city’s economy began to take off in the 1970s. It was the time when the HK government recognized the importance of Christmas Day celebrations by making the day a statutory holiday, granting employees the right to enjoy a holiday on either Winter Solstice Festival or Christmas Day.

When I arrived in the US to study for my first degree, I discovered that Christmas was an important time of the year for Americans to get together with family. Schools and offices would be closed for several days. The campus became deserted because everybody would have gone home. Fortunately I didn’t have to spend my first Christmas in the US alone, as I was invited by a friend of mine to spend time in his San Francisco home for a week. There I found out that ham is the traditional Christmas food in the US instead of the beloved turkey in Hong Kong (turkey is mainly for Thanksgiving in the US). When I went from Caltech to Stanford for my PhD studies, a new friend at Stanford also invited me to his SF home for the festive season. It is tangible proof that Christmas is a good time to open your homes and show hospitality and friendship.

In the US, as in HK and elsewhere in the developed world, Christmas has become a major annual commercial event when the most shopping money is spent and shopping malls enjoy brisk business. Even in China where Christmas is not a public holiday, this commercial aspect has taken roots in recent years especially in big cities like Beijing and Shanghai.

Christmas also provides a great opportunity for families to celebrate the holiday with their own special traditions. I remember every time when I returned from the US with my family to spend the festive season in Hong Kong, my Christmas-New Year traditions would be: family ‘yum cha”, a trip to the peak, strolling in Stanley and Shek O, and at night a walk down Temple Street and enjoying the Christmas lights and displays in Tsim Sha Tsui. It is ironic that for the last eight years, when I have actually lived in HK, I would get away during Christmas holidays to visit my children in the US. This year, they will be coming back to HK for Christmas for the first time in eight years, and we are looking forward to reviving our Christmas routine.

Speaking of Christmas lights, there is a bit of technology behind them. In the early days, the lights were generated by neon lights, which are essentially glass tubes containing neon gas and which would light up when electricity passes through it. More recently, they have mostly been replaced by LEDs. LED is a much more efficient light generator and much longer-lasting as well. For a long time, the only colors that LED can generate are infrared and green but not blue, which is the third missing primary color in order to create white light. This hurdle was finally overcome in 1993 when the first white-light LED was produced by three Japanese scientists who later won the 2014 Nobel in Physics for developing this breakthrough.

Sometimes I wonder what the Christmas of the future will look like. A recent Amazon report “Christmas of the future” contains predictions by two British futurists on what lies ahead at Christmas in 15-20 years. They predict that technology will add a whole new dimension to the Christmas experience, from food and drink to entertainment, gifting and decorations. In the future, we might be able to enjoy holographic displays of Christmas artwork and family and friends, haptic hugs, hydroponic home grown Christmas trees, virtual reality gift packaging. Festive foods will feature specialties from around the world and some will even be printable using 3D printers.

But let’s remember the most important part of Christmas: the human dimension. It is a happy occasion for get-togethers of family and friends that do not necessarily celebrate the religious aspects but love and friendship. That will probably remain unchanged for the foreseeable future.