Where did the saying '420' come from?

In 1971 a group of San Rafael High School students, called the Waldos, used to gather around 4:20pm to smoke marijuana, so "420" became the slang for signifying the time to light up. It later evolved into a term for potheads or just for the drug itself.

Coincidentally, it was Hitler's birthday. But it is an urban legend that there is any connection.

There are also rumors that 420 was a police code for a marijuana violation, but this is unproven.

Snopes has quite a bit to say about 420. See Related Links

Answer

In Europe we say the day of the month first, hence Hitler's birthday would be 20/4 so definitely no correlation.

It is actually from American marijuana smokers. It means to get high on the day 4/20 at 4:20.

Answer

4/20 is when a bunch of people joined together at 4:20 to smoke marijuana. Nowadays people on 4/20 at 4:20 smoke marijuana so they can legalize it