By Sam Shead, CNBC • Updated on December 24, 2020 at 10:32 am What to Know Zoom is preparing for what could end up being its busiest day ever. Around the world, lockdowns will make traveling to see friends and family on Christmas Day complicated, and for millions, illegal. Over 18 million people in the U.K. found out on Saturday that they can no longer see their loved ones on Christmas Day as Prime Minister Boris Johnson announced strict new rules. Zoom is gearing up for what could end up being its busiest day ever: Christmas Day. Around the world, lockdowns will make traveling to see friends and family on Christmas Day complicated, and for millions, illegal.