So far the majority of people trying to explain the 20th of April are incorrect. Being in Canada for this national 'day' today I have become interested in wanting to know more.
420’s origin IS known.
The term 420 originated at San Rafael High School, in 1971, among a group of about a dozen pot-smoking wiseacres who called themselves the Waldos, who are now pushing 50. The term was shorthand for the time of day the group would meet, at the campus statue of Louis Pasteur, to smoke pot. Intent on developing their own discreet language, they made 420 code for a time to get high, and its use spread among members of an entire generation.
So there you go, someone’s parents out there invented the term 4/20.
And remember this: There are NOT 420 chemicals in Weed. It’s about 315, the number goes up or down depending on what you are smoking. 4/20 is NOT police code or Maryjane. And that whole shit about Holland and 4/20 over there being “tea time” for smokers isn’t true either. It's just a national appreciate weed day, spread the good vibes!