420 is the day that celebrates marijuana and the push for legalizing cannabis. There are many stories around why this day has become a trend and how it got started. The most popular is that it started as a ritual by a group of high-schoolers in the 1970s where they would meet and smoke marijuana every day at 4:20pm. This ritual spread and 420 became code for smoking weed. There is even a website documenting how it got started. So of course it had to be converted to a calendar date to celebrate this legacy!