On Christmas Eve people sing the carol 'Silent Night'.
Tips
culture
In China, a folk tradition has emerged of giving a wrapped apple (苹果) on Christmas Eve because 苹 (píng) sounds like 平 in 平安 ('peace, safety'). These gift apples are called 平安果 and sold in decorative boxes.
memory
平安 means 'peace and safety' + 夜 'night' — the 'night of peace', matching the English original 'Silent/Holy Night'.