4:20

Whether you know a lot or a little about marijuana, chances are you've heard that the numbers 420 are especially significant in weed culture. But what does it mean? And why do grass fans consider April 20 and 4:20 so sacred? According to Time magazine, the number 420 dates back to 1971, when a group of five students from San Rafael High School in Marin County, California, began meeting at 4:20 p.m. to smoke marijuana. The actual numbers "420" don't have much symbolic meaning, Time reported in 2016. Rather, the students — Steve Capper, Dave Reddix, Jeffrey Noel, Larry Schwartz and Mark Gravich — chose to meet at 4:20 p.m. because by that time extracurricular activities were usually over.