Today marked the annual, unofficial international pot smoking day. (April 20 is written as 4/20 here in the States. 420 in all its forms, is code for smoking pot).
And where did the use of 420 (say ‘four-twenty’) come from? The term was coined in 1971 by a group of five San Rafael High School friends known as the Waldos, by virtue of their meeting time of 4:20 pm to smoke pot. Not long after that, 420 became a general code word for smoking pot.