"420" explained

Since April 20 (4/20) occurred this past week, there were many references to "420" that may have seemed obscure.  Here is the context:

420, 4:20 or 4/20 refers to consumption of cannabis and, by extension, a way to identify oneself with cannabis subculture... The term was coined from a group of teenagers at San Rafael High School in San Rafael, California, United States in 1971.  The teens would meet after school at 4:20 p.m. to smoke marijuana outside the school.