4/20 in Denver, Colorado
Fast Eddy Aki’a of Hawaii smokes a joint as thousands gathered to celebrate the state’s medicinal marijuana laws and collectively light up at 4:20 p.m. in Civic Center Park in Denver, on April 20, 2012. Marc Piscotty/Getty Images

April 20 may just seem like any other day, but to pot smokers and marijuana enthusiasts around the world, 4/20, or National Weed Day, is a time to celebrate — and consume — cannabis.

The counterculture holiday may not appear on any official calendar, but it’s widely popular nonetheless. Its origins can be traced to the 1970s in Northern California, where pot smokers began using the term “420” — the police code for Marijuana Smoking in Progress — as a reference to toking up. For those planning to observe 4/20, here’s a list of funny and inspirational quotes about marijuana from various artists, activists, politicians and business moguls:

“That is not a drug. It’s a leaf.” — Arnold Schwarzenegger

“When I was a kid, I inhaled frequently. That was the point.” — Barack Obama

“Not only do I think marijuana should be legalized ... I think it should be mandatory.” — Bill Hicks

“It grows naturally on our planet, serves a thousand different functions, all of them positive. To make marijuana against the law is like saying God made a big mistake.” — Bill Hicks

Medical marijuana
A bowl of medicinal marijuana is displayed at the International Cannabis and Hemp Expo at the Cow Palace in Daly City, California, on April 18, 2010. Justin Sullivan/Getty Images

“When you smoke the herb, it reveals you to yourself.” — Bob Marley

“Herb is the healing of a nation, alcohol is the destruction.” — Bob Marley

“Music and herb go together.” — Bob Marley

“If everybody smoked a blunt, relieve the mind, the world could be a better place.” — “Weed Song” by Bone Thugs-N-Harmony

“When I need to free my mind I can find satisfaction in a bag of weed. Everything I need, leave it to the trees.” — “Weed Song” by Bone Thugs-N-Harmony

“Marijuana saved my life. I have no doubts about it and you don’t need to show me any data.” — Greg Scott

4/20 in Denver, Colorado
A supporter of legalized marijuana holds up a blunt as thousands gathered to celebrate the state’s medicinal marijuana laws and collectively light up at 4:20 p.m. in Civic Center Park in Denver, on April 20, 2012. Marc Piscotty/Getty Images

“Smoking helped put me in touch with the realm of the senses.” — Hugh Hefner

“If you substitute marijuana for tobacco and alcohol, you’ll add eight to 24 years to your life.” — Jack Herer

“Forty million Americans smoked marijuana; the only ones who didn’t like it were Judge Ginsberg, Clarence Thomas and Bill Clinton.” — Jay Leno

“Just hit the blunt one time and see if it don’t change your perception on what’s important in your life.” — Katt Williams

“It really puzzles me to see marijuana connected with narcotics dope and all of that stuff. It is a thousand times better than whiskey. It is an assistant and a friend.” — Louis Armstrong

“Of course I know how to roll a joint.” — Martha Stewart

Cannabis plant
This file picture taken in London on Oct. 8, 2007, shows a cannabis plant. Leon Neal/AFP/Getty Images

“Instead of taking five or six of the prescriptions, I decided to go a natural route and smoke marijuana.” — Melissa Etheridge

“Is marijuana addictive? Yes, in the sense that most of the really pleasant things in life are worth endlessly repeating.” — Richard Neville

“They’ve outlawed the No. 1 vegetable on the planet.” — Timothy Leary

“Stop killing each other, man. Let’s just smoke a blunt.” — Tupac

“The biggest killer on the planet is stress and I still think the best medicine is and always has been cannabis.” — Willie Nelson

“I think people need to be educated to the fact that marijuana is not a drug. Marijuana is an herb and a flower. God put it here. If He put it here and He wants it to grow, what gives the government the right to say that God is wrong?” — Willie Nelson