Boxing Day 2024 is here, but not all Americans understand the meaning of the holiday celebrated in countries like the U.K.

Despite the name, Boxing Day has little to do with packaging or a jab-cross-hook combo. The holiday, most famously celebrated in the U.K. and its commonwealth, has its roots in kindness and goodwill.

Boxing Day, the traditionally British holiday recognized the day after Christmas, offers an extension of the festivities. People in countries like Canada, the U.K. and South Africa spend an extra ...